diff --git a/documentation/content/en/articles/pam/_index.adoc b/documentation/content/en/articles/pam/_index.adoc index 8aa56bb4b2..011ee465c9 100644 --- a/documentation/content/en/articles/pam/_index.adoc +++ b/documentation/content/en/articles/pam/_index.adoc @@ -1,700 +1,700 @@ --- title: Pluggable Authentication Modules authors: - author: Dag-Erling Smørgrav copyright: 2001-2003 Networks Associates Technology, Inc. description: A guide to the PAM system and modules under FreeBSD trademarks: ["pam", "freebsd", "linux", "opengroup", "sun", "general"] tags: ["pam", "introduction", "authentication", "modules", "FreeBSD"] --- //// Copyright (c) 2001-2003 Networks Associates Technology, Inc. All rights reserved. This software was developed for the FreeBSD Project by ThinkSec AS and Network Associates Laboratories, the Security Research Division of Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS research program. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. The name of the author may not be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. //// = Pluggable Authentication Modules :doctype: article :toc: macro :toclevels: 1 :icons: font :sectnums: :sectnumlevels: 6 :source-highlighter: rouge :experimental: :images-path: articles/pam/ ifdef::env-beastie[] ifdef::backend-html5[] include::shared/authors.adoc[] include::shared/mirrors.adoc[] include::shared/releases.adoc[] include::shared/attributes/attributes-{{% lang %}}.adoc[] include::shared/{{% lang %}}/teams.adoc[] include::shared/{{% lang %}}/mailing-lists.adoc[] include::shared/{{% lang %}}/urls.adoc[] :imagesdir: ../../../images/{images-path} :include-path: static/source/articles/pam/ endif::[] ifdef::backend-pdf,backend-epub3[] :include-path: ../../../../static/source/articles/pam/ include::../../../../shared/asciidoctor.adoc[] endif::[] endif::[] ifndef::env-beastie[] :include-path: ../../../../static/source/articles/pam/ include::../../../../../shared/asciidoctor.adoc[] endif::[] [.abstract-title] Abstract This article describes the underlying principles and mechanisms of the Pluggable Authentication Modules (PAM) library, and explains how to configure PAM, how to integrate PAM into applications, and how to write PAM modules. ''' toc::[] [[pam-intro]] == Introduction The Pluggable Authentication Modules (PAM) library is a generalized API for authentication-related services which allows a system administrator to add new authentication methods simply by installing new PAM modules, and to modify authentication policies by editing configuration files. PAM was defined and developed in 1995 by Vipin Samar and Charlie Lai of Sun Microsystems, and has not changed much since. In 1997, the Open Group published the X/Open Single Sign-on (XSSO) preliminary specification, which standardized the PAM API and added extensions for single (or rather integrated) sign-on. At the time of this writing, this specification has not yet been adopted as a standard. Although this article focuses primarily on FreeBSD 5.x, which uses OpenPAM, it should be equally applicable to FreeBSD 4.x, which uses Linux-PAM, and other operating systems such as Linux and Solaris(TM). [[pam-terms]] == Terms and Conventions [[pam-definitions]] === Definitions The terminology surrounding PAM is rather confused. Neither Samar and Lai's original paper nor the XSSO specification made any attempt at formally defining terms for the various actors and entities involved in PAM, and the terms that they do use (but do not define) are sometimes misleading and ambiguous. The first attempt at establishing a consistent and unambiguous terminology was a whitepaper written by Andrew G. Morgan (author of Linux-PAM) in 1999. While Morgan's choice of terminology was a huge leap forward, it is in this author's opinion by no means perfect. What follows is an attempt, heavily inspired by Morgan, to define precise and unambiguous terms for all actors and entities involved in PAM. account:: The set of credentials the applicant is requesting from the arbitrator. applicant:: The user or entity requesting authentication. arbitrator:: The user or entity who has the privileges necessary to verify the applicant's credentials and the authority to grant or deny the request. chain:: A sequence of modules that will be invoked in response to a PAM request. The chain includes information about the order in which to invoke the modules, what arguments to pass to them, and how to interpret the results. client:: The application responsible for initiating an authentication request on behalf of the applicant and for obtaining the necessary authentication information from him. facility:: One of the four basic groups of functionality provided by PAM: authentication, account management, session management and authentication token update. module:: A collection of one or more related functions implementing a particular authentication facility, gathered into a single (normally dynamically loadable) binary file and identified by a single name. policy:: The complete set of configuration statements describing how to handle PAM requests for a particular service. A policy normally consists of four chains, one for each facility, though some services do not use all four facilities. server:: The application acting on behalf of the arbitrator to converse with the client, retrieve authentication information, verify the applicant's credentials and grant or deny requests. service:: A class of servers providing similar or related functionality and requiring similar authentication. PAM policies are defined on a per-service basis, so all servers that claim the same service name will be subject to the same policy. session:: The context within which service is rendered to the applicant by the server. One of PAM's four facilities, session management, is concerned exclusively with setting up and tearing down this context. token:: A chunk of information associated with the account, such as a password or passphrase, which the applicant must provide to prove his identity. transaction:: A sequence of requests from the same applicant to the same instance of the same server, beginning with authentication and session set-up and ending with session tear-down. [[pam-usage-examples]] === Usage Examples This section aims to illustrate the meanings of some of the terms defined above by way of a handful of simple examples. ==== Client and Server Are One This simple example shows `alice` man:su[1]'ing to `root`. [source,shell] .... % whoami alice % ls -l `which su` -r-sr-xr-x 1 root wheel 10744 Dec 6 19:06 /usr/bin/su % su - Password: xi3kiune # whoami root .... * The applicant is `alice`. * The account is `root`. * The man:su[1] process is both client and server. * The authentication token is `xi3kiune`. * The arbitrator is `root`, which is why man:su[1] is setuid `root`. ==== Client and Server Are Separate The example below shows `eve` try to initiate an man:ssh[1] connection to `login.example.com`, ask to log in as `bob`, and succeed. Bob should have chosen a better password! [source,shell] .... % whoami eve % ssh bob@login.example.com bob@login.example.com's password: % god Last login: Thu Oct 11 09:52:57 2001 from 192.168.0.1 Copyright (c) 1980, 1983, 1986, 1988, 1990, 1991, 1993, 1994 The Regents of the University of California. All rights reserved. FreeBSD 4.4-STABLE (LOGIN) 4: Tue Nov 27 18:10:34 PST 2001 Welcome to FreeBSD! % .... * The applicant is `eve`. * The client is Eve's man:ssh[1] process. * The server is the man:sshd[8] process on `login.example.com` * The account is `bob`. * The authentication token is `god`. * Although this is not shown in this example, the arbitrator is `root`. ==== Sample Policy The following is FreeBSD's default policy for `sshd`: [.programlisting] .... sshd auth required pam_nologin.so no_warn sshd auth required pam_unix.so no_warn try_first_pass sshd account required pam_login_access.so sshd account required pam_unix.so sshd session required pam_lastlog.so no_fail sshd password required pam_permit.so .... * This policy applies to the `sshd` service (which is not necessarily restricted to the man:sshd[8] server.) * `auth`, `account`, `session` and `password` are facilities. * [.filename]#pam_nologin.so#, [.filename]#pam_unix.so#, [.filename]#pam_login_access.so#, [.filename]#pam_lastlog.so# and [.filename]#pam_permit.so# are modules. It is clear from this example that [.filename]#pam_unix.so# provides at least two facilities (authentication and account management.) [[pam-essentials]] == PAM Essentials [[pam-facilities-primitives]] === Facilities and Primitives The PAM API offers six different authentication primitives grouped in four facilities, which are described below. `auth`:: _Authentication._ This facility concerns itself with authenticating the applicant and establishing the account credentials. It provides two primitives: ** man:pam_authenticate[3] authenticates the applicant, usually by requesting an authentication token and comparing it with a value stored in a database or obtained from an authentication server. ** man:pam_setcred[3] establishes account credentials such as user ID, group membership and resource limits. `account`:: _Account management._ This facility handles non-authentication-related issues of account availability, such as access restrictions based on the time of day or the server's work load. It provides a single primitive: ** man:pam_acct_mgmt[3] verifies that the requested account is available. `session`:: _Session management._ This facility handles tasks associated with session set-up and tear-down, such as login accounting. It provides two primitives: ** man:pam_open_session[3] performs tasks associated with session set-up: add an entry in the [.filename]#utmp# and [.filename]#wtmp# databases, start an SSH agent, etc. ** man:pam_close_session[3] performs tasks associated with session tear-down: add an entry in the [.filename]#utmp# and [.filename]#wtmp# databases, stop the SSH agent, etc. `password`:: _Password management._ This facility is used to change the authentication token associated with an account, either because it has expired or because the user wishes to change it. It provides a single primitive: ** man:pam_chauthtok[3] changes the authentication token, optionally verifying that it is sufficiently hard to guess, has not been used previously, etc. [[pam-modules]] === Modules Modules are a very central concept in PAM; after all, they are the "M" in "PAM". A PAM module is a self-contained piece of program code that implements the primitives in one or more facilities for one particular mechanism; possible mechanisms for the authentication facility, for instance, include the UNIX(R) password database, NIS, LDAP and Radius. [[pam-module-naming]] ==== Module Naming FreeBSD implements each mechanism in a single module, named `pam_mechanism.so` (for instance, `pam_unix.so` for the UNIX(R) mechanism.) Other implementations sometimes have separate modules for separate facilities, and include the facility name as well as the mechanism name in the module name. To name one example, Solaris(TM) has a `pam_dial_auth.so.1` module which is commonly used to authenticate dialup users. [[pam-module-versioning]] ==== Module Versioning FreeBSD's original PAM implementation, based on Linux-PAM, did not use version numbers for PAM modules. This would commonly cause problems with legacy applications, which might be linked against older versions of the system libraries, as there was no way to load a matching version of the required modules. OpenPAM, on the other hand, looks for modules that have the same version number as the PAM library (currently 2), and only falls back to an unversioned module if no versioned module could be loaded. Thus legacy modules can be provided for legacy applications, while allowing new (or newly built) applications to take advantage of the most recent modules. Although Solaris(TM) PAM modules commonly have a version number, they are not truly versioned, because the number is a part of the module name and must be included in the configuration. [[pam-chains-policies]] === Chains and Policies When a server initiates a PAM transaction, the PAM library tries to load a policy for the service specified in the man:pam_start[3] call. The policy specifies how authentication requests should be processed, and is defined in a configuration file. This is the other central concept in PAM: the possibility for the admin to tune the system security policy (in the wider sense of the word) simply by editing a text file. A policy consists of four chains, one for each of the four PAM facilities. Each chain is a sequence of configuration statements, each specifying a module to invoke, some (optional) parameters to pass to the module, and a control flag that describes how to interpret the return code from the module. Understanding the control flags is essential to understanding PAM configuration files. There are four different control flags: `binding`:: If the module succeeds and no earlier module in the chain has failed, the chain is immediately terminated and the request is granted. If the module fails, the rest of the chain is executed, but the request is ultimately denied. + This control flag was introduced by Sun in Solaris(TM) 9 (SunOS(TM) 5.9), and is also supported by OpenPAM. `required`:: If the module succeeds, the rest of the chain is executed, and the request is granted unless some other module fails. If the module fails, the rest of the chain is also executed, but the request is ultimately denied. `requisite`:: If the module succeeds, the rest of the chain is executed, and the request is granted unless some other module fails. If the module fails, the chain is immediately terminated and the request is denied. `sufficient`:: If the module succeeds and no earlier module in the chain has failed, the chain is immediately terminated and the request is granted. If the module fails, the module is ignored and the rest of the chain is executed. + As the semantics of this flag may be somewhat confusing, especially when it is used for the last module in a chain, it is recommended that the `binding` control flag be used instead if the implementation supports it. `optional`:: The module is executed, but its result is ignored. If all modules in a chain are marked `optional`, all requests will always be granted. When a server invokes one of the six PAM primitives, PAM retrieves the chain for the facility the primitive belongs to, and invokes each of the modules listed in the chain, in the order they are listed, until it reaches the end, or determines that no further processing is necessary (either because a `binding` or `sufficient` module succeeded, or because a `requisite` module failed.) The request is granted if and only if at least one module was invoked, and all non-optional modules succeeded. Note that it is possible, though not very common, to have the same module listed several times in the same chain. For instance, a module that looks up user names and passwords in a directory server could be invoked multiple times with different parameters specifying different directory servers to contact. PAM treat different occurrences of the same module in the same chain as different, unrelated modules. [[pam-transactions]] === Transactions The lifecycle of a typical PAM transaction is described below. Note that if any of these steps fails, the server should report a suitable error message to the client and abort the transaction. . If necessary, the server obtains arbitrator credentials through a mechanism independent of PAM-most commonly by virtue of having been started by `root`, or of being setuid `root`. . The server calls man:pam_start[3] to initialize the PAM library and specify its service name and the target account, and register a suitable conversation function. . The server obtains various information relating to the transaction (such as the applicant's user name and the name of the host the client runs on) and submits it to PAM using man:pam_set_item[3]. . The server calls man:pam_authenticate[3] to authenticate the applicant. . The server calls man:pam_acct_mgmt[3] to verify that the requested account is available and valid. If the password is correct but has expired, man:pam_acct_mgmt[3] will return `PAM_NEW_AUTHTOK_REQD` instead of `PAM_SUCCESS`. . If the previous step returned `PAM_NEW_AUTHTOK_REQD`, the server now calls man:pam_chauthtok[3] to force the client to change the authentication token for the requested account. . Now that the applicant has been properly authenticated, the server calls man:pam_setcred[3] to establish the credentials of the requested account. It is able to do this because it acts on behalf of the arbitrator, and holds the arbitrator's credentials. . Once the correct credentials have been established, the server calls man:pam_open_session[3] to set up the session. . The server now performs whatever service the client requested-for instance, provide the applicant with a shell. . Once the server is done serving the client, it calls man:pam_close_session[3] to tear down the session. . Finally, the server calls man:pam_end[3] to notify the PAM library that it is done and that it can release whatever resources it has allocated in the course of the transaction. [[pam-config]] == PAM Configuration [[pam-config-file]] === PAM Policy Files [[pam-config-pam.conf]] ==== The [.filename]#/etc/pam.conf# The traditional PAM policy file is [.filename]#/etc/pam.conf#. This file contains all the PAM policies for your system. Each line of the file describes one step in a chain, as shown below: [.programlisting] .... login auth required pam_nologin.so no_warn .... The fields are, in order: service name, facility name, control flag, module name, and module arguments. Any additional fields are interpreted as additional module arguments. A separate chain is constructed for each service / facility pair, so while the order in which lines for the same service and facility appear is significant, the order in which the individual services and facilities are listed is not. The examples in the original PAM paper grouped configuration lines by facility, and the Solaris(TM) stock [.filename]#pam.conf# still does that, but FreeBSD's stock configuration groups configuration lines by service. Either way is fine; either way makes equal sense. [[pam-config-pam.d]] ==== The [.filename]#/etc/pam.d# OpenPAM and Linux-PAM support an alternate configuration mechanism, which is the preferred mechanism in FreeBSD. In this scheme, each policy is contained in a separate file bearing the name of the service it applies to. These files are stored in [.filename]#/etc/pam.d/#. These per-service policy files have only four fields instead of [.filename]#pam.conf#'s five: the service name field is omitted. Thus, instead of the sample [.filename]#pam.conf# line from the previous section, one would have the following line in [.filename]#/etc/pam.d/login#: [.programlisting] .... auth required pam_nologin.so no_warn .... As a consequence of this simplified syntax, it is possible to use the same policy for multiple services by linking each service name to a same policy file. For instance, to use the same policy for the `su` and `sudo` services, one could do as follows: [source,shell] .... # cd /etc/pam.d # ln -s su sudo .... This works because the service name is determined from the file name rather than specified in the policy file, so the same file can be used for multiple differently-named services. Since each service's policy is stored in a separate file, the [.filename]#pam.d# mechanism also makes it very easy to install additional policies for third-party software packages. [[pam-config-file-order]] ==== The Policy Search Order As we have seen above, PAM policies can be found in a number of places. What happens if policies for the same service exist in multiple places? It is essential to understand that PAM's configuration system is centered on chains. [[pam-config-breakdown]] === Breakdown of a Configuration Line As explained in <>, each line in [.filename]#/etc/pam.conf# consists of four or more fields: the service name, the facility name, the control flag, the module name, and zero or more module arguments. The service name is generally (though not always) the name of the application the statement applies to. If you are unsure, refer to the individual application's documentation to determine what service name it uses. Note that if you use [.filename]#/etc/pam.d/# instead of [.filename]#/etc/pam.conf#, the service name is specified by the name of the policy file, and omitted from the actual configuration lines, which then start with the facility name. The facility is one of the four facility keywords described in <>. Likewise, the control flag is one of the four keywords described in <>, describing how to interpret the return code from the module. Linux-PAM supports an alternate syntax that lets you specify the action to associate with each possible return code, but this should be avoided as it is non-standard and closely tied in with the way Linux-PAM dispatches service calls (which differs greatly from the way Solaris(TM) and OpenPAM do it.) Unsurprisingly, OpenPAM does not support this syntax. [[pam-policies]] === Policies To configure PAM correctly, it is essential to understand how policies are interpreted. When an application calls man:pam_start[3], the PAM library loads the policy for the specified service and constructs four module chains (one for each facility.) If one or more of these chains are empty, the corresponding chains from the policy for the `other` service are substituted. When the application later calls one of the six PAM primitives, the PAM library retrieves the chain for the corresponding facility and calls the appropriate service function in each module listed in the chain, in the order in which they were listed in the configuration. After each call to a service function, the module type and the error code returned by the service function are used to determine what happens next. With a few exceptions, which we discuss below, the following table applies: .PAM Chain Execution Summary [cols="1,1,1,1", options="header"] |=== | | PAM_SUCCESS | PAM_IGNORE | other |binding |if (!fail) break; |- |fail = true; |required |- |- |fail = true; |requisite |- |- |fail = true; break; |sufficient |if (!fail) break; |- |- |optional |- |- |- |=== If `fail` is true at the end of a chain, or when a "break" is reached, the dispatcher returns the error code returned by the first module that failed. Otherwise, it returns `PAM_SUCCESS`. The first exception of note is that the error code `PAM_NEW_AUTHTOK_REQD` is treated like a success, except that if no module failed, and at least one module returned `PAM_NEW_AUTHTOK_REQD`, the dispatcher will return `PAM_NEW_AUTHTOK_REQD`. The second exception is that man:pam_setcred[3] treats `binding` and `sufficient` modules as if they were `required`. The third and final exception is that man:pam_chauthtok[3] runs the entire chain twice (once for preliminary checks and once to actually set the password), and in the preliminary phase it treats `binding` and `sufficient` modules as if they were `required`. [[pam-freebsd-modules]] == FreeBSD PAM Modules [[pam-modules-deny]] === man:pam_deny[8] The man:pam_deny[8] module is one of the simplest modules available; it responds to any request with `PAM_AUTH_ERR`. It is useful for quickly disabling a service (add it to the top of every chain), or for terminating chains of `sufficient` modules. [[pam-modules-echo]] === man:pam_echo[8] The man:pam_echo[8] module simply passes its arguments to the conversation function as a `PAM_TEXT_INFO` message. It is mostly useful for debugging, but can also serve to display messages such as "Unauthorized access will be prosecuted" before starting the authentication procedure. [[pam-modules-exec]] === man:pam_exec[8] The man:pam_exec[8] module takes its first argument to be the name of a program to execute, and the remaining arguments are passed to that program as command-line arguments. One possible application is to use it to run a program at login time which mounts the user's home directory. [[pam-modules-ftpusers]] === man:pam_ftpusers[8] The man:pam_ftpusers[8] module [[pam-modules-group]] === man:pam_group[8] The man:pam_group[8] module accepts or rejects applicants on the basis of their membership in a particular file group (normally `wheel` for man:su[1]). It is primarily intended for maintaining the traditional behavior of BSD man:su[1], but has many other uses, such as excluding certain groups of users from a particular service. [[pam-modules-guest]] === man:pam_guest[8] The man:pam_guest[8] module allows guest logins using fixed login names. Various requirements can be placed on the password, but the default behavior is to allow any password as long as the login name is that of a guest account. The man:pam_guest[8] module can easily be used to implement anonymous FTP logins. [[pam-modules-krb5]] === man:pam_krb5[8] The man:pam_krb5[8] module [[pam-modules-ksu]] === man:pam_ksu[8] The man:pam_ksu[8] module [[pam-modules-lastlog]] === man:pam_lastlog[8] The man:pam_lastlog[8] module [[pam-modules-login-access]] === man:pam_login_access[8] The man:pam_login_access[8] module provides an implementation of the account management primitive which enforces the login restrictions specified in the man:login.access[5] table. [[pam-modules-nologin]] === man:pam_nologin[8] The man:pam_nologin[8] module refuses non-root logins when [.filename]#/var/run/nologin# exists. This file is normally created by man:shutdown[8] when less than five minutes remain until the scheduled shutdown time. [[pam-modules-opie]] === man:pam_opie[8] The man:pam_opie[8] module implements the man:opie[4] authentication method. The man:opie[4] system is a challenge-response mechanism where the response to each challenge is a direct function of the challenge and a passphrase, so the response can be easily computed "just in time" by anyone possessing the passphrase, eliminating the need for password lists. Moreover, since man:opie[4] never reuses a challenge that has been correctly answered, it is not vulnerable to replay attacks. [[pam-modules-opieaccess]] === man:pam_opieaccess[8] The man:pam_opieaccess[8] module is a companion module to man:pam_opie[8]. Its purpose is to enforce the restrictions codified in man:opieaccess[5], which regulate the conditions under which a user who would normally authenticate herself using man:opie[4] is allowed to use alternate methods. This is most often used to prohibit the use of password authentication from untrusted hosts. In order to be effective, the man:pam_opieaccess[8] module must be listed as `requisite` immediately after a `sufficient` entry for man:pam_opie[8], and before any other modules, in the `auth` chain. [[pam-modules-passwdqc]] === man:pam_passwdqc[8] The man:pam_passwdqc[8] module [[pam-modules-permit]] === man:pam_permit[8] The man:pam_permit[8] module is one of the simplest modules available; it responds to any request with `PAM_SUCCESS`. It is useful as a placeholder for services where one or more chains would otherwise be empty. [[pam-modules-radius]] === man:pam_radius[8] The man:pam_radius[8] module [[pam-modules-rhosts]] === man:pam_rhosts[8] The man:pam_rhosts[8] module [[pam-modules-rootok]] === man:pam_rootok[8] The man:pam_rootok[8] module reports success if and only if the real user id of the process calling it (which is assumed to be run by the applicant) is 0. This is useful for non-networked services such as man:su[1] or man:passwd[1], to which the `root` should have automatic access. [[pam-modules-securetty]] === man:pam_securetty[8] The man:pam_securetty[8] module [[pam-modules-self]] === man:pam_self[8] The man:pam_self[8] module reports success if and only if the names of the applicant matches that of the target account. It is most useful for non-networked services such as man:su[1], where the identity of the applicant can be easily verified. [[pam-modules-ssh]] === man:pam_ssh[8] The man:pam_ssh[8] module provides both authentication and session services. The authentication service allows users who have passphrase-protected SSH secret keys in their [.filename]#~/.ssh# directory to authenticate themselves by typing their passphrase. The session service starts man:ssh-agent[1] and preloads it with the keys that were decrypted in the authentication phase. -This feature is particularly useful for local logins, whether in X (using man:xdm[1] or another PAM-aware X login manager) or at the console. +This feature is particularly useful for local logins, whether in X (using man:xdm[8] or another PAM-aware X login manager) or at the console. [[pam-modules-tacplus]] === man:pam_tacplus[8] The man:pam_tacplus[8] module [[pam-modules-unix]] === man:pam_unix[8] The man:pam_unix[8] module implements traditional UNIX(R) password authentication, using man:getpwnam[3] to obtain the target account's password and compare it with the one provided by the applicant. It also provides account management services (enforcing account and password expiration times) and password-changing services. This is probably the single most useful module, as the great majority of admins will want to maintain historical behavior for at least some services. [[pam-appl-prog]] == PAM Application Programming This section has not yet been written. [[pam-module-prog]] == PAM Module Programming This section has not yet been written. :sectnums!: [appendix] [[pam-sample-appl]] == Sample PAM Application The following is a minimal implementation of man:su[1] using PAM. Note that it uses the OpenPAM-specific man:openpam_ttyconv[3] conversation function, which is prototyped in [.filename]#security/openpam.h#. If you wish build this application on a system with a different PAM library, you will have to provide your own conversation function. A robust conversation function is surprisingly difficult to implement; the one presented in <> is a good starting point, but should not be used in real-world applications. [.programlisting] .... include::{include-path}su.c[] .... :sectnums!: [appendix] [[pam-sample-module]] == Sample PAM Module The following is a minimal implementation of man:pam_unix[8], offering only authentication services. It should build and run with most PAM implementations, but takes advantage of OpenPAM extensions if available: note the use of man:pam_get_authtok[3], which enormously simplifies prompting the user for a password. [.programlisting] .... include::{include-path}pam_unix.c[] .... :sectnums!: [appendix] [[pam-sample-conv]] == Sample PAM Conversation Function The conversation function presented below is a greatly simplified version of OpenPAM's man:openpam_ttyconv[3]. It is fully functional, and should give the reader a good idea of how a conversation function should behave, but it is far too simple for real-world use. Even if you are not using OpenPAM, feel free to download the source code and adapt man:openpam_ttyconv[3] to your uses; we believe it to be as robust as a tty-oriented conversation function can reasonably get. [.programlisting] .... include::{include-path}converse.c[] .... :sectnums!: [[pam-further]] == Further Reading === Papers Making Login Services Independent of Authentication Technologies Vipin Samar. Charlie Lai. Sun Microsystems. _link:https://pubs.opengroup.org/onlinepubs/8329799/toc.htm[X/Open Single Sign-on Preliminary Specification]_. The Open Group. 1-85912-144-6. June 1997. _link:https://mirrors.kernel.org/pub/linux/libs/pam/pre/doc/draft-morgan-pam-07.txt[Pluggable Authentication Modules]_. Andrew G. Morgan. 1999-10-06. === User Manuals _link:https://docs.oracle.com/cd/E26505_01/html/E27224/pam-1.html[PAM Administration]_. Sun Microsystems. === Related Web Pages _link:https://www.openpam.org/[OpenPAM homepage]_ Dag-Erling Smørgrav. ThinkSec AS. _link:http://www.kernel.org/pub/linux/libs/pam/[Linux-PAM homepage]_ Andrew Morgan. _Solaris PAM homepage_. Sun Microsystems. diff --git a/documentation/content/en/books/faq/_index.adoc b/documentation/content/en/books/faq/_index.adoc index b66099da8d..5f989378e9 100644 --- a/documentation/content/en/books/faq/_index.adoc +++ b/documentation/content/en/books/faq/_index.adoc @@ -1,3208 +1,3208 @@ --- title: Frequently Asked Questions for FreeBSD 12.X and 13.X authors: - author: The FreeBSD Documentation Project copyright: 1995-2021 The FreeBSD Documentation Project description: Frequently Asked Questions, and answers, covering all aspects of FreeBSD trademarks: ["freebsd", "ibm", "ieee", "adobe", "intel", "linux", "microsoft", "opengroup", "sun", "netbsd", "general"] bookOrder: 5 tags: ["FAQ", "FreeBSD FAQ"] --- = Frequently Asked Questions for FreeBSD {rel2-relx} and {rel-relx} :doctype: book :toc: macro :toclevels: 1 :icons: font :sectnums: :sectnumlevels: 6 :partnums: :source-highlighter: rouge :experimental: :images-path: books/faq/ :rel-numbranch: 4 :rel-head: 14-CURRENT :rel-head-relx: 14.X :rel-head-releng: head/ :rel-relx: 13.X :rel-stable: 13-STABLE :rel-releng: stable/13/ :rel-relengdate: December 2018 :rel2-relx: 12.X :rel2-stable: 12-STABLE :rel2-releng: stable/12/ :rel2-relengdate: December 2018 ifdef::env-beastie[] ifdef::backend-html5[] include::shared/authors.adoc[] include::shared/mirrors.adoc[] include::shared/releases.adoc[] include::shared/attributes/attributes-{{% lang %}}.adoc[] include::shared/{{% lang %}}/teams.adoc[] include::shared/{{% lang %}}/mailing-lists.adoc[] include::shared/{{% lang %}}/urls.adoc[] endif::[] ifdef::backend-pdf,backend-epub3[] include::../../../../../shared/asciidoctor.adoc[] endif::[] endif::[] ifndef::env-beastie[] include::../../../../../shared/asciidoctor.adoc[] endif::[] [.abstract-title] Abstract This is the Frequently Asked Questions (FAQ) for FreeBSD versions {rel-relx} and {rel2-relx}. Every effort has been made to make this FAQ as informative as possible; if you have any suggestions as to how it may be improved, send them to the {freebsd-doc}. The latest version of this document is always available from the extref:{faq}[FreeBSD website]. It may also be downloaded as one large link:.[HTML] file with HTTP or as a variety of other formats from the https://download.freebsd.org/doc/[FreeBSD FTP server]. ''' toc::[] [[introduction]] == Introduction [[what-is-FreeBSD]] === What is FreeBSD? FreeBSD is a modern operating system for desktops, laptops, servers, and embedded systems with support for a large number of https://www.FreeBSD.org/platforms/[platforms]. It is based on U.C. Berkeley's "4.4BSD-Lite" release, with some "4.4BSD-Lite2" enhancements. It is also based indirectly on William Jolitz's port of U.C. Berkeley's "Net/2" to the i386(TM), known as "386BSD", though very little of the 386BSD code remains. FreeBSD is used by companies, Internet Service Providers, researchers, computer professionals, students and home users all over the world in their work, education and recreation. For more detailed information on FreeBSD, refer to the extref:{handbook}[FreeBSD Handbook]. [[FreeBSD-goals]] === What is the goal of the FreeBSD Project? The goal of the FreeBSD Project is to provide a stable and fast general purpose operating system that may be used for any purpose without strings attached. [[bsd-license-restrictions]] === Does the FreeBSD license have any restrictions? Yes. Those restrictions do not control how the code is used, but how to treat the FreeBSD Project itself. The license itself is available at https://www.FreeBSD.org/copyright/freebsd-license/[license] and can be summarized like this: * Do not claim that you wrote this. * Do not sue us if it breaks. * Do not remove or modify the license. Many of us have a significant investment in the project and would certainly not mind a little financial compensation now and then, but we definitely do not insist on it. We believe that our first and foremost "mission" is to provide code to any and all comers, and for whatever purpose, so that the code gets the widest possible use and provides the widest possible benefit. This, we believe, is one of the most fundamental goals of Free Software and one that we enthusiastically support. Code in our source tree which falls under the https://www.FreeBSD.org/copyright/COPYING[GNU General Public License (GPL)] or https://www.FreeBSD.org/copyright/COPYING.LIB[GNU Library General Public License (LGPL)] comes with slightly more strings attached, though at least on the side of enforced access rather than the usual opposite. Due to the additional complexities that can evolve in the commercial use of GPL software, we do, however, endeavor to replace such software with submissions under the more relaxed https://www.FreeBSD.org/copyright/freebsd-license/[FreeBSD license] whenever possible. [[replace-current-OS]] === Can FreeBSD replace my current operating system? For most people, yes. But this question is not quite that cut-and-dried. Most people do not actually use an operating system. They use applications. The applications are what really use the operating system. FreeBSD is designed to provide a robust and full-featured environment for applications. It supports a wide variety of web browsers, office suites, email readers, graphics programs, programming environments, network servers, and much more. Most of these applications can be managed through the https://www.FreeBSD.org/ports/[Ports Collection]. If an application is only available on one operating system, that operating system cannot just be replaced. Chances are, there is a very similar application on FreeBSD, however. As a solid office or Internet server or a reliable workstation, FreeBSD will almost certainly do everything you need. Many computer users across the world, including both novices and experienced UNIX(R) administrators, use FreeBSD as their only desktop operating system. Users migrating to FreeBSD from another UNIX(R)-like environment will find FreeBSD to be similar. Windows(R) and Mac OS(R) users may be interested in instead using https://www.ghostbsd.org/[GhostBSD], https://www.midnightbsd.org/[MidnightBSD] or https://www.nomadbsd.org/[NomadBSD] three FreeBSD-based desktop distributions. Non-UNIX(R) users should expect to invest some additional time learning the UNIX(R) way of doing things. This FAQ and the extref:{handbook}[FreeBSD Handbook] are excellent places to start. [[why-called-FreeBSD]] === Why is it called FreeBSD? * It may be used free of charge, even by commercial users. * Full source for the operating system is freely available, and the minimum possible restrictions have been placed upon its use, distribution and incorporation into other work (commercial or non-commercial). * Anyone who has an improvement or bug fix is free to submit their code and have it added to the source tree (subject to one or two obvious provisions). It is worth pointing out that the word "free" is being used in two ways here: one meaning "at no cost" and the other meaning "do whatever you like". Apart from one or two things you _cannot_ do with the FreeBSD code, for example pretending you wrote it, you can really do whatever you like with it. [[differences-to-other-bsds]] === What are the differences between FreeBSD and NetBSD, OpenBSD, and other open source BSD operating systems? James Howard wrote a good explanation of the history and differences between the various projects, called https://jameshoward.us/archive/bsd-family-tree/[The BSD Family Tree] which goes a fair way to answering this question. Some of the information is out of date, but the history portion in particular remains accurate. Most of the BSDs share patches and code, even today. All of the BSDs have common ancestry. The design goals of FreeBSD are described in <>, above. The design goals of the other most popular BSDs may be summarized as follows: * OpenBSD aims for operating system security above all else. The OpenBSD team wrote man:ssh[1] and man:pf[4], which have both been ported to FreeBSD. * NetBSD aims to be easily ported to other hardware platforms. * DragonFly BSD is a fork of FreeBSD 4.8 that has since developed many interesting features of its own, including the HAMMER file system and support for user-mode "vkernels". [[latest-version]] === What is the latest version of FreeBSD? At any point in the development of FreeBSD, there can be multiple parallel branches. {rel-relx} releases are made from the {rel-stable} branch, and {rel2-relx} releases are made from the {rel2-stable} branch. Up until the release of 12.0, the {rel2-relx} series was the one known as _-STABLE_. However, as of {rel-head-relx}, the {rel2-relx} branch will be designated for an "extended support" status and receive only fixes for major problems, such as security-related fixes. Releases are made <>. While many people stay more up-to-date with the FreeBSD sources (see the questions on <> and <>) than that, doing so is more of a commitment, as the sources are a moving target. More information on FreeBSD releases can be found on the https://www.FreeBSD.org/releng/#release-build[Release Engineering page] and in man:release[7]. [[current]] === What is _FreeBSD-CURRENT_? extref:{handbook}[FreeBSD-CURRENT, current] is the development version of the operating system, which will in due course become the new FreeBSD-STABLE branch. As such, it is really only of interest to developers working on the system and die-hard hobbyists. See the extref:{handbook}[relevant section, current] in the extref:{handbook}[Handbook] for details on running _-CURRENT_. Users not familiar with FreeBSD should not use FreeBSD-CURRENT. This branch sometimes evolves quite quickly and due to mistake can be un-buildable at times. People that use FreeBSD-CURRENT are expected to be able to analyze, debug, and report problems. [[stable]] === What is the FreeBSD-STABLE concept? _FreeBSD-STABLE_ is the development branch from which major releases are made. Changes go into this branch at a slower pace and with the general assumption that they have first been tested in FreeBSD-CURRENT. However, at any given time, the sources for FreeBSD-STABLE may or may not be suitable for general use, as it may uncover bugs and corner cases that were not yet found in FreeBSD-CURRENT. Users who do not have the resources to perform testing should instead run the most recent release of FreeBSD. _FreeBSD-CURRENT_, on the other hand, has been one unbroken line since 2.0 was released. For more detailed information on branches see "extref:{releng}[FreeBSD Release Engineering: Creating the Release Branch, rel-branch]", the status of the branches and the upcoming release schedule can be found on the https://www.FreeBSD.org/releng[Release Engineering Information] page. Version https://download.FreeBSD.org/releases/amd64/amd64/{rel121-current}-RELEASE/[{rel121-current}] is the latest release from the {rel-stable} branch; it was released in {rel121-current-date}. Version https://download.FreeBSD.org/releases/amd64/amd64/{rel113-current}-RELEASE/[{rel113-current}] is the latest release from the {rel2-stable} branch; it was released in {rel113-current-date}. [[release-freq]] === When are FreeBSD releases made? The {re} releases a new major version of FreeBSD about every 18 months and a new minor version about every 8 months, on average. Release dates are announced well in advance, so that the people working on the system know when their projects need to be finished and tested. A testing period precedes each release, to ensure that the addition of new features does not compromise the stability of the release. Many users regard this caution as one of the best things about FreeBSD, even though waiting for all the latest goodies to reach _-STABLE_ can be a little frustrating. More information on the release engineering process (including a schedule of upcoming releases) can be found on the https://www.FreeBSD.org/releng/[release engineering] pages on the FreeBSD Web site. For people who need or want a little more excitement, binary snapshots are made weekly as discussed above. [[snapshot-freq]] === When are FreeBSD snapshots made? FreeBSD link:https://www.FreeBSD.org/snapshots/[snapshot] releases are made based on the current state of the _-CURRENT_ and _-STABLE_ branches. The goals behind each snapshot release are: * To test the latest version of the installation software. * To give people who would like to run _-CURRENT_ or _-STABLE_ but who do not have the time or bandwidth to follow it on a day-to-day basis an easy way of bootstrapping it onto their systems. * To preserve a fixed reference point for the code in question, just in case we break something really badly later. (Although Subversion normally prevents anything horrible like this happening.) * To ensure that all new features and fixes in need of testing have the greatest possible number of potential testers. No claims are made that any _-CURRENT_ snapshot can be considered "production quality" for any purpose. If a stable and fully tested system is needed, stick to full releases. Snapshot releases are directly available from link:https://www.FreeBSD.org/snapshots/[snapshot]. Official snapshots are generated on a regular basis for all actively developed branches. [[responsible]] === Who is responsible for FreeBSD? The key decisions concerning the FreeBSD project, such as the overall direction of the project and who is allowed to add code to the source tree, are made by a link:https://www.FreeBSD.org/administration#t-core[core team] of 9 people. There is a much larger team of more than 350 extref:{contributors}[committers, staff-committers] who are authorized to make changes directly to the FreeBSD source tree. However, most non-trivial changes are discussed in advance in the <>, and there are no restrictions on who may take part in the discussion. [[where-get]] === Where can I get FreeBSD? Every significant release of FreeBSD is available via anonymous FTP from the https://download.FreeBSD.org/releases/[FreeBSD FTP site]: * The latest {rel-stable} release, {rel121-current}-RELEASE can be found in the https://download.FreeBSD.org/releases/amd64/amd64/{rel121-current}-RELEASE/[{rel121-current}-RELEASE directory]. * link:https://www.FreeBSD.org/snapshots/[Snapshot] releases are made monthly for the <> and <> branch, these being of service purely to bleeding-edge testers and developers. * The latest {rel2-stable} release, {rel113-current}-RELEASE can be found in the https://download.FreeBSD.org/releases/amd64/amd64/{rel113-current}-RELEASE/[{rel113-current}-RELEASE directory]. Information about obtaining FreeBSD on CD, DVD, and other media can be found in extref:{handbook}[the Handbook, mirrors]. [[access-pr]] === How do I access the Problem Report database? The Problem Report database of all user change requests may be queried by using our web-based PR https://bugs.FreeBSD.org/search/[query] interface. The link:https://www.FreeBSD.org/support/bugreports[web-based problem report submission interface] can be used to submit problem reports through a web browser. Before submitting a problem report, read extref:{problem-reports}[Writing FreeBSD Problem Reports], an article on how to write good problem reports. [[support]] == Documentation and Support [[books]] === What good books are there about FreeBSD? The project produces a wide range of documentation, available online from this link: https://www.FreeBSD.org/docs/[https://www.FreeBSD.org/docs/]. [[doc-formats]] === Is the documentation available in other formats, such as plain text (ASCII), or PDF? Yes. The documentation is available in a number of different formats and compression schemes on the FreeBSD FTP site, in the https://download.freebsd.org/doc/[/doc/] directory. The documentation is categorized in a number of different ways. These include: * The document's name, such as `faq`, or `handbook`. * The document's language and encoding. These are based on the locale names found under [.filename]#/usr/share/locale# on a FreeBSD system. The current languages and encodings are as follows: + [.informaltable] [cols="1,1", frame="none", options="header"] |=== | Name | Meaning |`en_US.ISO8859-1` |English (United States) |`bn_BD.ISO10646-1` |Bengali or Bangla (Bangladesh) |`da_DK.ISO8859-1` |Danish (Denmark) |`de_DE.ISO8859-1` |German (Germany) |`el_GR.ISO8859-7` |Greek (Greece) |`es_ES.ISO8859-1` |Spanish (Spain) |`fr_FR.ISO8859-1` |French (France) |`hu_HU.ISO8859-2` |Hungarian (Hungary) |`it_IT.ISO8859-15` |Italian (Italy) |`ja_JP.eucJP` |Japanese (Japan, EUC encoding) |`ko_KR.UTF-8` |Korean (Korea, UTF-8 encoding) |`mn_MN.UTF-8` |Mongolian (Mongolia, UTF-8 encoding) |`nl_NL.ISO8859-1` |Dutch (Netherlands) |`pl_PL.ISO8859-2` |Polish (Poland) |`pt_BR.ISO8859-1` |Portuguese (Brazil) |`ru_RU.KOI8-R` |Russian (Russia, KOI8-R encoding) |`tr_TR.ISO8859-9` |Turkish (Turkey) |`zh_CN.UTF-8` |Simplified Chinese (China, UTF-8 encoding) |`zh_TW.UTF-8` |Traditional Chinese (Taiwan, UTF-8 encoding) |=== + [NOTE] ==== Some documents may not be available in all languages. ==== * The document's format. We produce the documentation in a number of different output formats. Each format has its own advantages and disadvantages. Some formats are better suited for online reading, while others are meant to be aesthetically pleasing when printed on paper. Having the documentation available in any of these formats ensures that our readers will be able to read the parts they are interested in, either on their monitor, or on paper after printing the documents. The currently available formats are: + [.informaltable] [cols="1,1", frame="none", options="header"] |=== | Format | Meaning |`html-split` |A collection of small, linked, HTML files. |`html` |One large HTML file containing the entire document |`pdf` |Adobe's Portable Document Format |`txt` |Plain text |=== * The compression and packaging scheme. .. Where the format is `html-split`, the files are bundled up using man:tar[1]. The resulting [.filename]#.tar# is then compressed using the compression schemes detailed in the next point. .. All the other formats generate one file. For example, [.filename]#article.pdf#, [.filename]#book.html#, and so on. + These files are then compressed using either the `zip` or `bz2` compression schemes. man:tar[1] can be used to uncompress these files. + So the PDF version of the Handbook, compressed using `bzip2` will be stored in a file called [.filename]#book.pdf.bz2# in the [.filename]#handbook/# directory. After choosing the format and compression mechanism, download the compressed files, uncompress them, and then copy the appropriate documents into place. For example, the split HTML version of the FAQ, compressed using man:bzip2[1], can be found in [.filename]#doc/en_US.ISO8859-1/books/faq/book.html-split.tar.bz2# To download and uncompress that file, type: [source,shell] .... # fetch https://download.freebsd.org/doc/en_US.ISO8859-1/books/faq/book.html-split.tar.bz2 # tar xvf book.html-split.tar.bz2 .... If the file is compressed, tar will automatically detect the appropriate format and decompress it correctly, resulting in a collection of [.filename]#.html# files. The main one is called [.filename]#index.html#, which will contain the table of contents, introductory material, and links to the other parts of the document. [[mailing]] === Where do I find info on the FreeBSD mailing lists? What FreeBSD news groups are available? Refer to the extref:{handbook}[Handbook entry on mailing-lists, eresources-mail] and the extref:{handbook}[Handbook entry on newsgroups, eresources-news]. [[irc]] === Are there FreeBSD IRC (Internet Relay Chat) channels? Yes, most major IRC networks host a FreeBSD chat channel and the FreeBSD wiki holds an up to date https://wiki.freebsd.org/IRC/Channels[list of IRC channels]. Each of these channels are distinct and are not connected to each other. Since their chat styles differ, try each to find one suited to your chat style. [[forums]] === Are there any web based forums to discuss FreeBSD? The official FreeBSD forums are located at https://forums.FreeBSD.org/[https://forums.FreeBSD.org/]. [[training]] === Where can I get commercial FreeBSD training and support? http://www.ixsystems.com[iXsystems, Inc.], parent company of the http://www.freebsdmall.com/[FreeBSD Mall], provides commercial FreeBSD and TrueOS software http://www.ixsystems.com/support[support], in addition to FreeBSD development and tuning solutions. BSD Certification Group, Inc. provides system administration certifications for DragonFly BSD, FreeBSD, NetBSD, and OpenBSD. Refer to http://www.BSDCertification.org[their site] for more information. Any other organizations providing training and support should contact the Project to be listed here. [[install]] == Installation [[which-architecture]] === Which platform should I download? I have a 64 bit capable Intel(R) CPU, but I only see amd64. amd64 is the term FreeBSD uses for 64-bit compatible x86 architectures (also known as "x86-64" or "x64"). Most modern computers should use amd64. Older hardware should use i386. When installing on a non-x86-compatible architecture, select the platform which best matches the hardware. [[floppy-download]] === Which file do I download to get FreeBSD? On the https://www.freebsd.org/where/[Getting FreeBSD] page, select `[iso]` next to the architecture that matches the hardware. Any of the following can be used: [.informaltable] [cols="1,1", frame="none", options="header"] |=== | file | description |[.filename]#disc1.iso# |Contains enough to install FreeBSD and a minimal set of packages. |[.filename]#dvd1.iso# |Similar to [.filename]#disc1.iso# but with additional packages. |[.filename]#memstick.img# |A bootable image sufficient for writing to a USB stick. |[.filename]#bootonly.iso# |A minimal image that requires network access during installation to completely install FreeBSD. |=== Full instructions on this procedure and a little bit more about installation issues in general can be found in the extref:{handbook}[Handbook entry on installing FreeBSD, bsdinstall]. [[floppy-image-too-large]] === What do I do if the install image does not boot? This can be caused by not downloading the image in _binary_ mode when using FTP. Some FTP clients default their transfer mode to _ascii_ and attempt to change any end-of-line characters received to match the conventions used by the client's system. This will almost invariably corrupt the boot image. Check the SHA-256 checksum of the downloaded boot image: if it is not _exactly_ that on the server, then the download process is suspect. When using a command line FTP client, type _binary_ at the FTP command prompt after getting connected to the server and before starting the download of the image. [[install-instructions-location]] === Where are the instructions for installing FreeBSD? Installation instructions can be found at extref:{handbook}[Handbook entry on installing FreeBSD, bsdinstall]. [[custom-boot-floppy]] === How can I make my own custom release or install disk? Customized FreeBSD installation media can be created by building a custom release. Follow the instructions in the extref:{releng}[Release Engineering] article. [[windows-coexist]] === Can Windows(R) co-exist with FreeBSD? (x86-specific) If Windows(R) is installed first, then yes. FreeBSD's boot manager will then manage to boot Windows(R) and FreeBSD. If Windows(R) is installed afterwards, it will overwrite the boot manager. If that happens, see the next section. [[bootmanager-restore]] === Another operating system destroyed my Boot Manager. How do I get it back? (x86-specific) This depends upon the boot manager. The FreeBSD boot selection menu can be reinstalled using man:boot0cfg[8]. For example, to restore the boot menu onto the disk _ada0_: [source,shell] .... # boot0cfg -B ada0 .... The non-interactive MBR bootloader can be installed using man:gpart[8]: [source,shell] .... # gpart bootcode -b /boot/mbr ada0 .... For more complex situations, including GPT disks, see man:gpart[8]. [[need-complete-sources]] === Do I need to install the source? In general, no. There is nothing in the base system which requires the presence of the source to operate. Some ports, like package:sysutils/lsof[], will not build unless the source is installed. In particular, if the port builds a kernel module or directly operates on kernel structures, the source must be installed. [[need-kernel]] === Do I need to build a kernel? Usually not. The supplied `GENERIC` kernel contains the drivers an ordinary computer will need. man:freebsd-update[8], the FreeBSD binary upgrade tool, cannot upgrade custom kernels, another reason to stick with the `GENERIC` kernel when possible. For computers with very limited RAM, such as embedded systems, it may be worthwhile to build a smaller custom kernel containing just the required drivers. [[password-encryption]] === Should I use DES, Blowfish, or MD5 passwords and how do I specify which form my users receive? FreeBSD uses _SHA512_ by default. DES passwords are still available for backwards compatibility with operating systems that still use the less secure password format. FreeBSD also supports the Blowfish and MD5 password formats. Which password format to use for new passwords is controlled by the `passwd_format` login capability in [.filename]#/etc/login.conf#, which takes values of `des`, `blf` (if these are available) or `md5`. See the man:login.conf[5] manual page for more information about login capabilities. [[ffs-limits]] === What are the limits for FFS file systems? For FFS file systems, the largest file system is practically limited by the amount of memory required to man:fsck[8] the file system. man:fsck[8] requires one bit per fragment, which with the default fragment size of 4 KB equates to 32 MB of memory per TB of disk. This does mean that on architectures which limit userland processes to 2 GB (e.g., i386(TM)), the maximum man:fsck[8]'able filesystem is ~60 TB. If there was not a man:fsck[8] memory limit the maximum filesystem size would be 2 ^ 64 (blocks) * 32 KB => 16 Exa * 32 KB => 512 ZettaBytes. The maximum size of a single FFS file is approximately 2 PB with the default block size of 32 KB. Each 32 KB block can point to 4096 blocks. With triple indirect blocks, the calculation is 32 KB * 12 + 32 KB * 4096 + 32 KB * 4096^2 + 32 KB * 4096^3. Increasing the block size to 64 KB will increase the max file size by a factor of 16. [[archsw-readin-failed-error]] === Why do I get an error message, readin failed after compiling and booting a new kernel? The world and kernel are out of sync. This is not supported. Be sure to use `make buildworld` and `make buildkernel` to update the kernel. Boot the system by specifying the kernel directly at the second stage, pressing any key when the `|` shows up before loader is started. [[general-configuration-tool]] === Is there a tool to perform post-installation configuration tasks? Yes. bsdconfig provides a nice interface to configure FreeBSD post-installation. [[hardware]] == Hardware Compatibility [[compatibility-general]] === General [[which-hardware-to-get]] ==== I want to get a piece of hardware for my FreeBSD system. Which model/brand/type is best? This is discussed continually on the FreeBSD mailing lists but is to be expected since hardware changes so quickly. Read through the Hardware Notes for FreeBSD link:{u-rel121-hardware}[{rel121-current}] or link:{u-rel113-hardware}[{rel113-current}] and search the mailing list https://www.FreeBSD.org/search/#mailinglists[archives] before asking about the latest and greatest hardware. Chances are a discussion about that type of hardware took place just last week. Before purchasing a laptop, check the archives for {freebsd-questions}, or possibly a specific mailing list for a particular hardware type. [[memory-upper-limitation]] ==== What are the limits for memory? FreeBSD as an operating system generally supports as much physical memory (RAM) as the platform it is running on does. Keep in mind that different platforms have different limits for memory; for example i386(TM) without PAE supports at most 4 GB of memory (and usually less than that because of PCI address space) and i386(TM) with PAE supports at most 64 GB memory. As of FreeBSD 10, AMD64 platforms support up to 4 TB of physical memory. [[memory-i386-over-4gb]] ==== Why does FreeBSD report less than 4 GB memory when installed on an i386(TM) machine? The total address space on i386(TM) machines is 32-bit, meaning that at most 4 GB of memory is addressable (can be accessed). Furthermore, some addresses in this range are reserved by hardware for different purposes, for example for using and controlling PCI devices, for accessing video memory, and so on. Therefore, the total amount of memory usable by the operating system for its kernel and applications is limited to significantly less than 4 GB. Usually, 3.2 GB to 3.7 GB is the maximum usable physical memory in this configuration. To access more than 3.2 GB to 3.7 GB of installed memory (meaning up to 4 GB but also more than 4 GB), a special tweak called PAE must be used. PAE stands for Physical Address Extension and is a way for 32-bit x86 CPUs to address more than 4 GB of memory. It remaps the memory that would otherwise be overlaid by address reservations for hardware devices above the 4 GB range and uses it as additional physical memory (see man:pae[4]). Using PAE has some drawbacks; this mode of memory access is a little bit slower than the normal (without PAE) mode and loadable modules (see man:kld[4]) are not supported. This means all drivers must be compiled into the kernel. The most common way to enable PAE is to build a new kernel with the special ready-provided kernel configuration file called [.filename]#PAE#, which is already configured to build a safe kernel. Note that some entries in this kernel configuration file are too conservative and some drivers marked as unready to be used with PAE are actually usable. A rule of thumb is that if the driver is usable on 64-bit architectures (like AMD64), it is also usable with PAE. When creating a custom kernel configuration file, PAE can be enabled by adding the following line: [.programlisting] .... options PAE .... PAE is not much used nowadays because most new x86 hardware also supports running in 64-bit mode, known as AMD64 or Intel(R) 64. It has a much larger address space and does not need such tweaks. FreeBSD supports AMD64 and it is recommended that this version of FreeBSD be used instead of the i386(TM) version if 4 GB or more memory is required. [[compatibility-processors]] === Architectures and Processors [[architectures]] ==== Does FreeBSD support architectures other than the x86? Yes. FreeBSD divides support into multiple tiers. Tier 1 architectures, such as i386 or amd64; are fully supported. Tiers 2 and 3 are supported on a best-effort basis. A full explanation of the tier system is available in the extref:{committers-guide}[Committer's Guide., archs] A complete list of supported architectures can be found on the https://www.FreeBSD.org/platforms/[platforms page.] [[smp-support]] ==== Does FreeBSD support Symmetric Multiprocessing (SMP)? FreeBSD supports symmetric multi-processor (SMP) on all non-embedded platforms (e.g, i386, amd64, etc.). SMP is also supported in arm and MIPS kernels, although some CPUs may not support this. FreeBSD's SMP implementation uses fine-grained locking, and performance scales nearly linearly with number of CPUs. man:smp[4] has more details. [[microcode]] ==== What is microcode? How do I install Intel(R) CPU microcode updates? Microcode is a method of programmatically implementing hardware level instructions. This allows for CPU bugs to be fixed without replacing the on board chip. Install package:sysutils/devcpu-data[], then add: [.programlisting] .... microcode_update_enable="YES" .... to [.filename]#/etc/rc.conf# [[compatibility-peripherals]] === Peripherals [[supported-peripherals]] ==== What kind of peripherals does FreeBSD support? See the complete list in the Hardware Notes for FreeBSD link:{u-rel121-hardware}[{rel121-current}] or link:{u-rel113-hardware}[{rel113-current}]. [[compatibility-kbd-mice]] === Keyboards and Mice [[moused]] ==== Is it possible to use a mouse outside the X Window system? The default console driver, man:vt[4], provides the ability to use a mouse pointer in text consoles to cut & paste text. Run the mouse daemon, man:moused[8], and turn on the mouse pointer in the virtual console: [source,shell] .... # moused -p /dev/xxxx -t yyyy # vidcontrol -m on .... Where _xxxx_ is the mouse device name and _yyyy_ is a protocol type for the mouse. The mouse daemon can automatically determine the protocol type of most mice, except old serial mice. Specify the `auto` protocol to invoke automatic detection. If automatic detection does not work, see the man:moused[8] manual page for a list of supported protocol types. For a PS/2 mouse, add `moused_enable="YES"` to [.filename]#/etc/rc.conf# to start the mouse daemon at boot time. Additionally, to use the mouse daemon on all virtual terminals instead of just the console, add `allscreens_flags="-m on"` to [.filename]#/etc/rc.conf#. When the mouse daemon is running, access to the mouse must be coordinated between the mouse daemon and other programs such as X Windows. Refer to the FAQ <> for more details on this issue. [[text-mode-cut-paste]] ==== How do I cut and paste text with a mouse in the text console? It is not possible to remove data using the mouse. However, it is possible to copy and paste. Once the mouse daemon is running as described in the <>, hold down button 1 (left button) and move the mouse to select a region of text. Then, press button 2 (middle button) to paste it at the text cursor. Pressing button 3 (right button) will "extend" the selected region of text. If the mouse does not have a middle button, it is possible to emulate one or remap buttons using mouse daemon options. See the man:moused[8] manual page for details. [[mouse-wheel-buttons]] ==== My mouse has a fancy wheel and buttons. Can I use them in FreeBSD? The answer is, unfortunately, "It depends". These mice with additional features require specialized driver in most cases. Unless the mouse device driver or the user program has specific support for the mouse, it will act just like a standard two, or three button mouse. For the possible usage of wheels in the X Window environment, refer to <>. [[keyboard-delete-key]] ==== How do I use my delete key in sh and csh? For the Bourne Shell, add the following lines to [.filename]#~/.shrc#. See man:sh[1] and man:editrc[5]. [.programlisting] .... bind ^[[3~ ed-delete-next-char # for xterm .... For the C Shell, add the following lines to [.filename]#~/.cshrc#. See man:csh[1]. [.programlisting] .... bindkey ^[[3~ delete-char # for xterm .... [[compatibility-other]] === Other Hardware [[es1370-silent-pcm]] ==== Workarounds for no sound from my man:pcm[4] sound card? Some sound cards set their output volume to 0 at every boot. Run the following command every time the machine boots: [source,shell] .... # mixer pcm 100 vol 100 cd 100 .... [[power-management-support]] ==== Does FreeBSD support power management on my laptop? FreeBSD supports the ACPI features found in modern hardware. Further information can be found in man:acpi[4]. [[troubleshoot]] == Troubleshooting [[pae]] === Why is FreeBSD finding the wrong amount of memory on i386(TM) hardware? The most likely reason is the difference between physical memory addresses and virtual addresses. The convention for most PC hardware is to use the memory area between 3.5 GB and 4 GB for a special purpose (usually for PCI). This address space is used to access PCI hardware. As a result real, physical memory cannot be accessed by that address space. What happens to the memory that should appear in that location is hardware dependent. Unfortunately, some hardware does nothing and the ability to use that last 500 MB of RAM is entirely lost. Luckily, most hardware remaps the memory to a higher location so that it can still be used. However, this can cause some confusion when watching the boot messages. On a 32-bit version of FreeBSD, the memory appears lost, since it will be remapped above 4 GB, which a 32-bit kernel is unable to access. In this case, the solution is to build a PAE enabled kernel. See the entry on memory limits for more information. On a 64-bit version of FreeBSD, or when running a PAE-enabled kernel, FreeBSD will correctly detect and remap the memory so it is usable. During boot, however, it may seem as if FreeBSD is detecting more memory than the system really has, due to the described remapping. This is normal and the available memory will be corrected as the boot process completes. [[signal11]] === Why do my programs occasionally die with Signal 11 errors? Signal 11 errors are caused when a process has attempted to access memory which the operating system has not granted it access to. If something like this is happening at seemingly random intervals, start investigating the cause. These problems can usually be attributed to either: . If the problem is occurring only in a specific custom application, it is probably a bug in the code. . If it is a problem with part of the base FreeBSD system, it may also be buggy code, but more often than not these problems are found and fixed long before us general FAQ readers get to use these bits of code (that is what -CURRENT is for). It is probably not a FreeBSD bug if the problem occurs compiling a program, but the activity that the compiler is carrying out changes each time. For example, if `make buildworld` fails while trying to compile [.filename]#ls.c# into [.filename]#ls.o# and, when run again, it fails in the same place, this is a broken build. Try updating source and try again. If the compile fails elsewhere, it is almost certainly due to hardware. In the first case, use a debugger such as man:gdb[1] to find the point in the program which is attempting to access a bogus address and fix it. In the second case, verify which piece of hardware is at fault. Common causes of this include: . The hard disks might be overheating: Check that the fans are still working, as the disk and other hardware might be overheating. . The processor running is overheating: This might be because the processor has been overclocked, or the fan on the processor might have died. In either case, ensure that the hardware is running at what it is specified to run at, at least while trying to solve this problem. If it is not, clock it back to the default settings.) + Regarding overclocking, it is far cheaper to have a slow system than a fried system that needs replacing! Also the community is not sympathetic to problems on overclocked systems. . Dodgy memory: if multiple memory SIMMS/DIMMS are installed, pull them all out and try running the machine with each SIMM or DIMM individually to narrow the problem down to either the problematic DIMM/SIMM or perhaps even a combination. . Over-optimistic motherboard settings: the BIOS settings, and some motherboard jumpers, provide options to set various timings. The defaults are often sufficient, but sometimes setting the wait states on RAM too low, or setting the "RAM Speed: Turbo" option will cause strange behavior. A possible idea is to set to BIOS defaults, after noting the current settings first. . Unclean or insufficient power to the motherboard. Remove any unused I/O boards, hard disks, or CD-ROMs, or disconnect the power cable from them, to see if the power supply can manage a smaller load. Or try another power supply, preferably one with a little more power. For instance, if the current power supply is rated at 250 Watts, try one rated at 300 Watts. Read the section on <> for a further explanation and a discussion on how memory testing software or hardware can still pass faulty memory. There is an extensive FAQ on this at http://www.bitwizard.nl/sig11/[the SIG11 problem FAQ]. Finally, if none of this has helped, it is possibly a bug in FreeBSD. Follow <> to send a problem report. [[trap-12-panic]] === My system crashes with either Fatal trap 12: page fault in kernel mode, or panic:, and spits out a bunch of information. What should I do? The FreeBSD developers are interested in these errors, but need more information than just the error message. Copy the full crash message. Then consult the FAQ section on <>, build a debugging kernel, and get a backtrace. This might sound difficult, but does not require any programming skills. Just follow the instructions. [[proc-table-full]] === What is the meaning of the error maxproc limit exceeded by uid %i, please see tuning(7) and login.conf(5)? The FreeBSD kernel will only allow a certain number of processes to exist at one time. The number is based on the `kern.maxusers` man:sysctl[8] variable. `kern.maxusers` also affects various other in-kernel limits, such as network buffers. If the machine is heavily loaded, increase `kern.maxusers`. This will increase these other system limits in addition to the maximum number of processes. To adjust the `kern.maxusers` value, see the extref:{handbook}[File/Process Limits, kern-maxfiles] section of the Handbook. While that section refers to open files, the same limits apply to processes. If the machine is lightly loaded but running a very large number of processes, adjust the `kern.maxproc` tunable by defining it in [.filename]#/boot/loader.conf#. The tunable will not get adjusted until the system is rebooted. For more information about tuning tunables, see man:loader.conf[5]. If these processes are being run by a single user, adjust `kern.maxprocperuid` to be one less than the new `kern.maxproc` value. It must be at least one less because one system program, man:init[8], must always be running. [[remote-fullscreen]] === Why do full screen applications on remote machines misbehave? The remote machine may be setting the terminal type to something other than `xterm` which is required by the FreeBSD console. Alternatively the kernel may have the wrong values for the width and height of the terminal. Check the value of the `TERM` environment variable is `xterm`. If the remote machine does not support that try `vt100`. Run `stty -a` to check what the kernel thinks the terminal dimensions are. If they are incorrect, they can be changed by running `stty rows _RR_ cols _CC_`. Alternatively, if the client machine has package:x11/xterm[] installed, then running `resize` will query the terminal for the correct dimensions and set them. [[connection-delay]] === Why does it take so long to connect to my computer via ssh or telnet? The symptom: there is a long delay between the time the TCP connection is established and the time when the client software asks for a password (or, in man:telnet[1]'s case, when a login prompt appears). The problem: more likely than not, the delay is caused by the server software trying to resolve the client's IP address into a hostname. Many servers, including the Telnet and SSH servers that come with FreeBSD, do this to store the hostname in a log file for future reference by the administrator. The remedy: if the problem occurs whenever connecting the client computer to any server, the problem is with the client. If the problem only occurs when someone connects to the server computer, the problem is with the server. If the problem is with the client, the only remedy is to fix the DNS so the server can resolve it. If this is on a local network, consider it a server problem and keep reading. If this is on the Internet, contact your ISP. If the problem is with the server on a local network, configure the server to resolve address-to-hostname queries for the local address range. See man:hosts[5] and man:named[8] for more information. If this is on the Internet, the problem may be that the local server's resolver is not functioning correctly. To check, try to look up another host such as `www.yahoo.com`. If it does not work, that is the problem. Following a fresh install of FreeBSD, it is also possible that domain and name server information is missing from [.filename]#/etc/resolv.conf#. This will often cause a delay in SSH, as the option `UseDNS` is set to `yes` by default in [.filename]#/etc/ssh/sshd_config#. If this is causing the problem, either fill in the missing information in [.filename]#/etc/resolv.conf# or set `UseDNS` to `no` in [.filename]#sshd_config# as a temporary workaround. [[file-table-full]] === Why does file: table is full show up repeatedly in man:dmesg[8]? This error message indicates that the number of available file descriptors have been exhausted on the system. Refer to the extref:{handbook}[kern.maxfiles, kern-maxfiles] section of the extref:{handbook}[Tuning Kernel Limits, configtuning-kernel-limits] section of the Handbook for a discussion and solution. [[computer-clock-skew]] === Why does the clock on my computer keep incorrect time? The computer has two or more clocks, and FreeBSD has chosen to use the wrong one. Run man:dmesg[8], and check for lines that contain `Timecounter`. The one with the highest quality value that FreeBSD chose. [source,shell] .... # dmesg | grep Timecounter Timecounter "i8254" frequency 1193182 Hz quality 0 Timecounter "ACPI-fast" frequency 3579545 Hz quality 1000 Timecounter "TSC" frequency 2998570050 Hz quality 800 Timecounters tick every 1.000 msec .... Confirm this by checking the `kern.timecounter.hardware` man:sysctl[3]. [source,shell] .... # sysctl kern.timecounter.hardware kern.timecounter.hardware: ACPI-fast .... It may be a broken ACPI timer. The simplest solution is to disable the ACPI timer in [.filename]#/boot/loader.conf#: [.programlisting] .... debug.acpi.disabled="timer" .... Or the BIOS may modify the TSC clock-perhaps to change the speed of the processor when running from batteries, or going into a power saving mode, but FreeBSD is unaware of these adjustments, and appears to gain or lose time. In this example, the `i8254` clock is also available, and can be selected by writing its name to the `kern.timecounter.hardware` man:sysctl[3]. [source,shell] .... # sysctl kern.timecounter.hardware=i8254 kern.timecounter.hardware: TSC -> i8254 .... The computer should now start keeping more accurate time. To have this change automatically run at boot time, add the following line to [.filename]#/etc/sysctl.conf#: [.programlisting] .... kern.timecounter.hardware=i8254 .... [[indefinite-wait-buffer]] === What does the error swap_pager: indefinite wait buffer: mean? This means that a process is trying to page memory from disk, and the page attempt has hung trying to access the disk for more than 20 seconds. It might be caused by bad blocks on the disk drive, disk wiring, cables, or any other disk I/O-related hardware. If the drive itself is bad, disk errors will appear in [.filename]#/var/log/messages# and in the output of `dmesg`. Otherwise, check the cables and connections. [[lock-order-reversal]] === What is a lock order reversal? The FreeBSD kernel uses a number of resource locks to arbitrate contention for certain resources. When multiple kernel threads try to obtain multiple resource locks, there's always the potential for a deadlock, where two threads have each obtained one of the locks and blocks forever waiting for the other thread to release one of the other locks. This sort of locking problem can be avoided if all threads obtain the locks in the same order. A run-time lock diagnostic system called man:witness[4], enabled in FreeBSD-CURRENT and disabled by default for stable branches and releases, detects the potential for deadlocks due to locking errors, including errors caused by obtaining multiple resource locks with a different order from different parts of the kernel. The man:witness[4] framework tries to detect this problem as it happens, and reports it by printing a message to the system console about a `lock order reversal` (often referred to also as LOR). It is possible to get false positives, as man:witness[4] is conservative. A true positive report _does not_ mean that a system is dead-locked; instead it should be understood as a warning that a deadlock could have happened here. [NOTE] ==== Problematic LORs tend to get fixed quickly, so check the {freebsd-current} before posting to it. ==== [[called-with-non-sleepable-locks-held]] === What does Called ... with the following non-sleepable locks held mean? This means that a function that may sleep was called while a mutex (or other unsleepable) lock was held. The reason this is an error is because mutexes are not intended to be held for long periods of time; they are supposed to only be held to maintain short periods of synchronization. This programming contract allows device drivers to use mutexes to synchronize with the rest of the kernel during interrupts. Interrupts (under FreeBSD) may not sleep. Hence it is imperative that no subsystem in the kernel block for an extended period while holding a mutex. To catch such errors, assertions may be added to the kernel that interact with the man:witness[4] subsystem to emit a warning or fatal error (depending on the system configuration) when a potentially blocking call is made while holding a mutex. In summary, such warnings are non-fatal, however with unfortunate timing they could cause undesirable effects ranging from a minor blip in the system's responsiveness to a complete system lockup. For additional information about locking in FreeBSD see man:locking[9]. [[touch-not-found]] === Why does buildworld/installworld die with the message touch: not found? This error does not mean that the man:touch[1] utility is missing. The error is instead probably due to the dates of the files being set sometime in the future. If the CMOS clock is set to local time, run `adjkerntz -i` to adjust the kernel clock when booting into single-user mode. [[applications]] == User Applications [[user-apps]] === Where are all the user applications? Refer to link:https://www.FreeBSD.org/ports/[the ports page] for info on software packages ported to FreeBSD. Most ports should work on all supported versions of FreeBSD. Those that do not are specifically marked as such. Each time a FreeBSD release is made, a snapshot of the ports tree at the time of release is also included in the [.filename]#ports/# directory. FreeBSD supports compressed binary packages to easily install and uninstall ports. Use man:pkg[7] to control the installation of packages. [[how-do-download-ports-tree]] === How do I download the Ports tree? Should I be using Git? See crossref:handbook[ports-using-installation-methods,Installing the Ports Collection]. [[ports-4x]] === Why can I not build this port on my {rel2-relx} -, or {rel-relx} -STABLE machine? If the installed FreeBSD version lags significantly behind _-CURRENT_ or _-STABLE_, update the Ports Collection using the instructions in extref:{handbook}[Using the Ports Collection, ports-using]. If the system is up-to-date, someone might have committed a change to the port which works for _-CURRENT_ but which broke the port for _-STABLE_. https://bugs.FreeBSD.org/submit/[Submit] a bug report, since the Ports Collection is supposed to work for both the _-CURRENT_ and _-STABLE_ branches. [[make-index]] === I just tried to build INDEX using make index, and it failed. Why? First, make sure that the Ports Collection is up-to-date. Errors that affect building [.filename]#INDEX# from an up-to-date copy of the Ports Collection are high-visibility and are thus almost always fixed immediately. There are rare cases where [.filename]#INDEX# will not build due to odd cases involving `OPTIONS_SET` being set in [.filename]#make.conf#. If you suspect that this is the case, try to make [.filename]#INDEX# with those variables turned off before reporting it to {freebsd-ports}. [[ports-update]] === I updated the sources, now how do I update my installed ports? FreeBSD does not include a port upgrading tool, but it does have some tools to make the upgrade process somewhat easier. Additional tools are available to simplify port handling and are described the extref:{handbook}[Upgrading Ports, ports-using] section in the FreeBSD Handbook. [[ports-major-upgrade]] === Do I need to recompile every port each time I perform a major version update? Yes! While a recent system will run with software compiled under an older release, things will randomly crash and fail to work once other ports are installed or updated. When the system is upgraded, various shared libraries, loadable modules, and other parts of the system will be replaced with newer versions. Applications linked against the older versions may fail to start or, in other cases, fail to function properly. For more information, see extref:{handbook}[the section on upgrades, freebsdupdate-upgrade] in the FreeBSD Handbook. [[ports-minor-upgrade]] === Do I need to recompile every port each time I perform a minor version update? In general, no. FreeBSD developers do their utmost to guarantee binary compatibility across all releases with the same major version number. Any exceptions will be documented in the Release Notes, and advice given there should be followed. [[minimal-sh]] === Why is /bin/sh so minimal? Why does FreeBSD not use bash or another shell? Many people need to write shell scripts which will be portable across many systems. That is why POSIX(R) specifies the shell and utility commands in great detail. Most scripts are written in Bourne shell (man:sh[1]), and because several important programming interfaces (man:make[1], man:system[3], man:popen[3], and analogues in higher-level scripting languages like Perl and Tcl) are specified to use the Bourne shell to interpret commands. As the Bourne shell is so often and widely used, it is important for it to be quick to start, be deterministic in its behavior, and have a small memory footprint. The existing implementation is our best effort at meeting as many of these requirements simultaneously as we can. To keep `/bin/sh` small, we have not provided many of the convenience features that other shells have. That is why other more featureful shells like `bash`, `scsh`, man:tcsh[1], and `zsh` are available. Compare the memory utilization of these shells by looking at the "VSZ" and "RSS" columns in a `ps -u` listing. [[kernelconfig]] == Kernel Configuration [[make-kernel]] === I would like to customize my kernel. Is it difficult? Not at all! Check out the extref:{handbook}[kernel config section of the Handbook, kernelconfig]. [NOTE] ==== The new [.filename]#kernel# will be installed to the [.filename]#/boot/kernel# directory along with its modules, while the old kernel and its modules will be moved to the [.filename]#/boot/kernel.old# directory. If a mistake is made in the configuration, simply boot the previous version of the kernel. ==== [[why-kernel-big]] === Why is my kernel so big? `GENERIC` kernels shipped with FreeBSD are compiled in _debug mode_. Kernels built in debug mode contain debug data in separate files that are used for debugging. FreeBSD releases prior to 11.0 store these debug files in the same directory as the kernel itself, [.filename]#/boot/kernel/#. In FreeBSD 11.0 and later the debug files are stored in [.filename]#/usr/lib/debug/boot/kernel/#. Note that there will be little or no performance loss from running a debug kernel, and it is useful to keep one around in case of a system panic. When running low on disk space, there are different options to reduce the size of [.filename]#/boot/kernel/# and [.filename]#/usr/lib/debug/#. To not install the symbol files, make sure the following line exists in [.filename]#/etc/src.conf#: [.programlisting] .... WITHOUT_KERNEL_SYMBOLS=yes .... For more information see man:src.conf[5]. If you want to avoid building debug files altogether, make sure that both of the following are true: * This line does not exist in the kernel configuration file: + [.programlisting] .... makeoptions DEBUG=-g .... * Do not run man:config[8] with `-g`. Either of the above settings will cause the kernel to be built in debug mode. To build and install only the specified modules, list them in [.filename]#/etc/make.conf#: [.programlisting] .... MODULES_OVERRIDE= accf_http ipfw .... Replace _accf_httpd ipfw_ with a list of needed modules. Only the listed modules will be built. This reduces the size of the kernel directory and decreases the amount of time needed to build the kernel. For more information, read [.filename]#/usr/share/examples/etc/make.conf#. Unneeded devices can be removed from the kernel to further reduce the size. See <> for more information. To put any of these options into effect, follow the instructions to extref:{handbook}[build and install, kernelconfig-building] the new kernel. For reference, the FreeBSD 11 amd64 kernel ([.filename]#/boot/kernel/kernel#) is approximately 25 MB. [[generic-kernel-build-failure]] === Why does every kernel I try to build fail to compile, even GENERIC? There are a number of possible causes for this problem: * The source tree is different from the one used to build the currently running system. When attempting an upgrade, read [.filename]#/usr/src/UPDATING#, paying particular attention to the "COMMON ITEMS" section at the end. * The `make buildkernel` did not complete successfully. The `make buildkernel` target relies on files generated by the `make buildworld` target to complete its job correctly. * Even when building <>, it is possible that the source tree was fetched at a time when it was either being modified or it was broken. Only releases are guaranteed to be buildable, although <> builds fine the majority of the time. Try re-fetching the source tree and see if the problem goes away. Try using a different mirror in case the previous one is having problems. [[scheduler-in-use]] === Which scheduler is in use on a running system? The name of the scheduler currently being used is directly available as the value of the `kern.sched.name` sysctl: [source,shell] .... % sysctl kern.sched.name kern.sched.name: ULE .... [[scheduler-kern-quantum]] === What is kern.sched.quantum? `kern.sched.quantum` is the maximum number of ticks a process can run without being preempted in the 4BSD scheduler. [[disks]] == Disks, File Systems, and Boot Loaders [[adding-disks]] === How can I add my new hard disk to my FreeBSD system? See the extref:{handbook}[Adding Disks, disks-adding] section in the FreeBSD Handbook. [[new-huge-disk]] === How do I move my system over to my huge new disk? The best way is to reinstall the operating system on the new disk, then move the user data over. This is highly recommended when tracking _-STABLE_ for more than one release or when updating a release instead of installing a new one. Install booteasy on both disks with man:boot0cfg[8] and dual boot until you are happy with the new configuration. Skip the next paragraph to find out how to move the data after doing this. Alternatively, partition and label the new disk with either man:sade[8] or man:gpart[8]. If the disks are MBR-formatted, booteasy can be installed on both disks with man:boot0cfg[8] so that the computer can dual boot to the old or new system after the copying is done. Once the new disk set up, the data cannot just be copied. Instead, use tools that understand device files and system flags, such as man:dump[8]. Although it is recommended to move the data while in single-user mode, it is not required. When the disks are formatted with UFS, never use anything but man:dump[8] and man:restore[8] to move the root file system. These commands should also be used when moving a single partition to another empty partition. The sequence of steps to use `dump` to move the data from one UFS partitions to a new partition is: [.procedure] ==== . `newfs` the new partition. . `mount` it on a temporary mount point. . `cd` to that directory. . `dump` the old partition, piping output to the new one. ==== For example, to move [.filename]#/dev/ada1s1a# with [.filename]#/mnt# as the temporary mount point, type: [source,shell] .... # newfs /dev/ada1s1a # mount /dev/ada1s1a /mnt # cd /mnt # dump 0af - / | restore rf - .... Rearranging partitions with `dump` takes a bit more work. To merge a partition like [.filename]#/var# into its parent, create the new partition large enough for both, move the parent partition as described above, then move the child partition into the empty directory that the first move created: [source,shell] .... # newfs /dev/ada1s1a # mount /dev/ada1s1a /mnt # cd /mnt # dump 0af - / | restore rf - # cd var # dump 0af - /var | restore rf - .... To split a directory from its parent, say putting [.filename]#/var# on its own partition when it was not before, create both partitions, then mount the child partition on the appropriate directory in the temporary mount point, then move the old single partition: [source,shell] .... # newfs /dev/ada1s1a # newfs /dev/ada1s1d # mount /dev/ada1s1a /mnt # mkdir /mnt/var # mount /dev/ada1s1d /mnt/var # cd /mnt # dump 0af - / | restore rf - .... The man:cpio[1] and man:pax[1] utilities are also available for moving user data. These are known to lose file flag information, so use them with caution. [[safe-softupdates]] === Which partitions can safely use Soft Updates? I have heard that Soft Updates on / can cause problems. What about Journaled Soft Updates? Short answer: Soft Updates can usually be safely used on all partitions. Long answer: Soft Updates has two characteristics that may be undesirable on certain partitions. First, a Soft Updates partition has a small chance of losing data during a system crash. The partition will not be corrupted as the data will simply be lost. Second, Soft Updates can cause temporary space shortages. When using Soft Updates, the kernel can take up to thirty seconds to write changes to the physical disk. When a large file is deleted the file still resides on disk until the kernel actually performs the deletion. This can cause a very simple race condition. Suppose one large file is deleted and another large file is immediately created. The first large file is not yet actually removed from the physical disk, so the disk might not have enough room for the second large file. This will produce an error that the partition does not have enough space, even though a large chunk of space has just been released. A few seconds later, the file creation works as expected. If a system should crash after the kernel accepts a chunk of data for writing to disk, but before that data is actually written out, data could be lost. This risk is extremely small, but generally manageable. These issues affect all partitions using Soft Updates. So, what does this mean for the root partition? Vital information on the root partition changes very rarely. If the system crashed during the thirty-second window after such a change is made, it is possible that data could be lost. This risk is negligible for most applications, but be aware that it exists. If the system cannot tolerate this much risk, do not use Soft Updates on the root file system! [.filename]#/# is traditionally one of the smallest partitions. If [.filename]#/tmp# is on [.filename]#/#, there may be intermittent space problems. Symlinking [.filename]#/tmp# to [.filename]#/var/tmp# will solve this problem. Finally, man:dump[8] does not work in live mode (-L) on a filesystem, with Journaled Soft Updates (SU+J). [[mount-foreign-fs]] === Can I mount other foreign file systems under FreeBSD? FreeBSD supports a variety of other file systems. UFS:: UFS CD-ROMs can be mounted directly on FreeBSD. Mounting disk partitions from Digital UNIX and other systems that support UFS may be more complex, depending on the details of the disk partitioning for the operating system in question. ext2/ext3:: FreeBSD supports `ext2fs`, `ext3fs`, and `ext4fs` partitions. See man:ext2fs[5] for more information. NTFS:: FUSE based NTFS support is available as a port (package:sysutils/fusefs-ntfs[]). For more information, see man:ntfs-3g[8]. FAT:: FreeBSD includes a read-write FAT driver. For more information, see man:mount_msdosfs[8]. ZFS:: FreeBSD includes a port of Sun(TM)'s ZFS driver. The current recommendation is to use it only on amd64 platforms with sufficient memory. For more information, see man:zfs[8]. FreeBSD includes the Network File System NFS and the FreeBSD Ports Collection provides several FUSE applications to support many other file systems. [[mount-dos]] === How do I mount a secondary DOS partition? The secondary DOS partitions are found after _all_ the primary partitions. For example, if `E` is the second DOS partition on the second SCSI drive, there will be a device file for "slice 5" in [.filename]#/dev#. To mount it: [source,shell] .... # mount -t msdosfs /dev/da1s5 /dos/e .... [[crypto-file-system]] === Is there a cryptographic file system for FreeBSD? Yes, man:gbde[8] and man:geli[8]. See the extref:{handbook}[Encrypting Disk Partitions, disks-encrypting] section of the FreeBSD Handbook. [[grub-loader]] === How do I boot FreeBSD and Linux(R) using GRUB? To boot FreeBSD using GRUB, add the following to either [.filename]#/boot/grub/menu.lst# or [.filename]#/boot/grub/grub.conf#, depending upon which is used by the Linux(R) distribution. [.programlisting] .... title FreeBSD 9.1 root (hd0,a) kernel /boot/loader .... Where _hd0,a_ points to the root partition on the first disk. To specify the slice number, use something like this _(hd0,2,a)_. By default, if the slice number is omitted, GRUB searches the first slice which has the `a` partition. [[booteasy-loader]] === How do I boot FreeBSD and Linux(R) using BootEasy? Install LILO at the start of the Linux(R) boot partition instead of in the Master Boot Record. Then boot LILO from BootEasy. This is recommended when running Windows(R) and Linux(R) as it makes it simpler to get Linux(R) booting again if Windows(R) is reinstalled. [[changing-bootprompt]] === How do I change the boot prompt from ??? to something more meaningful? This cannot be accomplished with the standard boot manager without rewriting it. There are a number of other boot managers in the [.filename]#sysutils# category of the Ports Collection. [[removable-drives]] === How do I use a new removable drive? If the drive already has a file system on it, use a command like this: [source,shell] .... # mount -t msdosfs /dev/da0s1 /mnt .... If the drive will only be used with FreeBSD systems, partition it with UFS or ZFS. This will provide long filename support, improvement in performance, and stability. If the drive will be used by other operating systems, a more portable choice, such as msdosfs, is better. [source,shell] .... # dd if=/dev/zero of=/dev/da0 count=2 # gpart create -s GPT /dev/da0 # gpart add -t freebsd-ufs /dev/da0 .... Finally, create a new file system: [source,shell] .... # newfs /dev/da0p1 .... and mount it: [source,shell] .... # mount /dev/da0s1 /mnt .... It is a good idea to add a line to [.filename]#/etc/fstab# (see man:fstab[5]) so you can just type `mount /mnt` in the future: [.programlisting] .... /dev/da0p1 /mnt ufs rw,noauto 0 0 .... [[mount-cd-superblock]] === Why do I get Incorrect super block when mounting a CD? The type of device to mount must be specified. This is described in the Handbook section on extref:{handbook}[Using Data CDs, mounting-cd]. [[cdrom-not-configured]] === Why do I get Device not configured when mounting a CD? This generally means that there is no CD in the drive, or the drive is not visible on the bus. Refer to the extref:{handbook}[Using Data CDs, mounting-cd] section of the Handbook for a detailed discussion of this issue. [[cdrom-unicode-filenames]] === Why do all non-English characters in filenames show up as ? on my CDs when mounted in FreeBSD? The CD probably uses the "Joliet" extension for storing information about files and directories. This is discussed in the Handbook section on extref:{handbook}[Using Data CD-ROMs, mounting-cd]. [[burncd-isofs]] === A CD burned under FreeBSD cannot be read under any other operating system. Why? This means a raw file was burned to the CD, rather than creating an ISO 9660 file system. Take a look at the Handbook section on extref:{handbook}[Using Data CDs]. [[copy-cd]] === How can I create an image of a data CD? This is discussed in the Handbook section on extref:{handbook}[Writing Data to an ISO File System, mkisofs]. For more on working with CD-ROMs, see the extref:{handbook}[Creating CDs Section, creating-cds] in the Storage chapter in the Handbook. [[mount-audio-CD]] === Why can I not mount an audio CD? Trying to mount an audio CD will produce an error like `cd9660: /dev/cd0: Invalid argument`. This is because `mount` only works on file systems. Audio CDs do not have file systems; they just have data. Instead, use a program that reads audio CDs, such as the package:audio/xmcd[] package or port. [[multi-session-CD]] === How do I mount a multi-session CD? By default, man:mount[8] will attempt to mount the last data track (session) of a CD. To load an earlier session, use the `-s` command line argument. Refer to man:mount_cd9660[8] for specific examples. [[user-floppymount]] === How do I let ordinary users mount CD-ROMs, DVDs, USB drives, and other removable media? As `root` set the sysctl variable `vfs.usermount` to `1`. [source,shell] .... # sysctl vfs.usermount=1 .... To make this persist across reboots, add the line `vfs.usermount=1` to [.filename]#/etc/sysctl.conf# so that it is reset at system boot time. Users can only mount devices they have read permissions to. To allow users to mount a device permissions must be set in [.filename]#/etc/devfs.conf#. For example, to allow users to mount the first USB drive add: [.programlisting] .... # Allow all users to mount a USB drive. own /dev/da0 root:operator perm /dev/da0 0666 .... All users can now mount devices they could read onto a directory that they own: [source,shell] .... % mkdir ~/my-mount-point % mount -t msdosfs /dev/da0 ~/my-mount-point .... Unmounting the device is simple: [source,shell] .... % umount ~/my-mount-point .... Enabling `vfs.usermount`, however, has negative security implications. A better way to access MS-DOS(R) formatted media is to use the package:emulators/mtools[] package in the Ports Collection. [NOTE] ==== The device name used in the previous examples must be changed according to the configuration. ==== [[du-vs-df]] === The du and df commands show different amounts of disk space available. What is going on? This is due to how these commands actually work. `du` goes through the directory tree, measures how large each file is, and presents the totals. `df` just asks the file system how much space it has left. They seem to be the same thing, but a file without a directory entry will affect `df` but not `du`. When a program is using a file, and the file is deleted, the file is not really removed from the file system until the program stops using it. The file is immediately deleted from the directory listing, however. As an example, consider a file large enough to affect the output of `du` and `df`. A file being viewed with `more` can be deleted without causing an error. The entry is removed from the directory so no other program or user can access it. However, `du` shows that it is gone as it has walked the directory tree and the file is not listed. `df` shows that it is still there, as the file system knows that `more` is still using that space. Once the `more` session ends, `du` and `df` will agree. This situation is common on web servers. Many people set up a FreeBSD web server and forget to rotate the log files. The access log fills up [.filename]#/var#. The new administrator deletes the file, but the system still complains that the partition is full. Stopping and restarting the web server program would free the file, allowing the system to release the disk space. To prevent this from happening, set up man:newsyslog[8]. Note that Soft Updates can delay the freeing of disk space and it can take up to 30 seconds for the change to be visible. [[add-swap-space]] === How can I add more swap space? This section extref:{handbook}[of the Handbook, adding-swap-space] describes how to do this. [[manufacturer-disk-size]] === Why does FreeBSD see my disk as smaller than the manufacturer says it is? Disk manufacturers calculate gigabytes as a billion bytes each, whereas FreeBSD calculates them as 1,073,741,824 bytes each. This explains why, for example, FreeBSD's boot messages will report a disk that supposedly has 80 GB as holding 76,319 MB. Also note that FreeBSD will (by default) <> 8% of the disk space. [[disk-more-than-full]] === How is it possible for a partition to be more than 100% full? A portion of each UFS partition (8%, by default) is reserved for use by the operating system and the `root` user. man:df[1] does not count that space when calculating the `Capacity` column, so it can exceed 100%. Notice that the `Blocks` column is always greater than the sum of the `Used` and `Avail` columns, usually by a factor of 8%. For more details, look up `-m` in man:tunefs[8]. [[all-about-zfs]] == ZFS [[how-much-ram-for-zfs]] === What is the minimum amount of RAM one should have to run ZFS? A minimum of 4GB of RAM is required for comfortable usage, but individual workloads can vary widely. [[what-is-zil]] === What is the ZIL and when does it get used? The ZIL (ZFS intent log) is a write log used to implement posix write commitment semantics across crashes. Normally writes are bundled up into transaction groups and written to disk when filled ("Transaction Group Commit"). However syscalls like man:fsync[2] require a commitment that the data is written to stable storage before returning. The ZIL is needed for writes that have been acknowledged as written but which are not yet on disk as part of a transaction. The transaction groups are timestamped. In the event of a crash the last valid timestamp is found and missing data is merged in from the ZIL. [[need-ssd-for-zil]] === Do I need a SSD for ZIL? By default, ZFS stores the ZIL in the pool with all the data. If an application has a heavy write load, storing the ZIL in a separate device that has very fast synchronous, sequential write performance can improve overall system performance. For other workloads, a SSD is unlikely to make much of an improvement. [[what-is-l2arc]] === What is the L2ARC? The L2ARC is a read cache stored on a fast device such as an SSD. This cache is not persistent across reboots. Note that RAM is used as the first layer of cache and the L2ARC is only needed if there is insufficient RAM. L2ARC needs space in the ARC to index it. So, perversely, a working set that fits perfectly in the ARC will not fit perfectly any more if a L2ARC is used because part of the ARC is holding the L2ARC index, pushing part of the working set into the L2ARC which is slower than RAM. [[should-enable-dedup]] === Is enabling deduplication advisable? Generally speaking, no. Deduplication takes up a significant amount of RAM and may slow down read and write disk access times. Unless one is storing data that is very heavily duplicated, such as virtual machine images or user backups, it is possible that deduplication will do more harm than good. Another consideration is the inability to revert deduplication status. If data is written when deduplication is enabled, disabling dedup will not cause those blocks which were deduplicated to be replicated until they are next modified. Deduplication can also lead to some unexpected situations. In particular, deleting files may become much slower. [[zpool-fully-full]] === I cannot delete or create files on my ZFS pool. How can I fix this? This could happen because the pool is 100% full. ZFS requires space on the disk to write transaction metadata. To restore the pool to a usable state, truncate the file to delete: [source,shell] .... % truncate -s 0 unimportant-file .... File truncation works because a new transaction is not started, new spare blocks are created instead. [NOTE] ==== On systems with additional ZFS dataset tuning, such as deduplication, the space may not be immediately available ==== [[zfs-ssd-trim]] === Does ZFS support TRIM for Solid State Drives? ZFS TRIM support was added to FreeBSD 10-CURRENT with revision link:https://svnweb.freebsd.org/changeset/base/240868[r240868]. ZFS TRIM support was added to all FreeBSD-STABLE branches in link:https://svnweb.freebsd.org/changeset/base/252162[r252162] and link:https://svnweb.freebsd.org/changeset/base/251419[r251419], respectively. ZFS TRIM is enabled by default, and can be turned off by adding this line to [.filename]#/etc/sysctl.conf#: [.programlisting] .... vfs.zfs.trim.enabled=0 .... [NOTE] ==== ZFS TRIM support was added to GELI as of link:https://svnweb.freebsd.org/changeset/base/286444[r286444]. Please see man:geli[8] and the `-T` switch. ==== [[admin]] == System Administration [[startup-config-files]] === Where are the system start-up configuration files? The primary configuration file is [.filename]#/etc/defaults/rc.conf# which is described in man:rc.conf[5]. System startup scripts such as [.filename]#/etc/rc# and [.filename]#/etc/rc.d#, which are described in man:rc[8], include this file. _Do not edit this file!_ Instead, to edit an entry in [.filename]#/etc/defaults/rc.conf#, copy the line into [.filename]#/etc/rc.conf# and change it there. For example, to start man:sshd[8], the included OpenSSH daemon: [source,shell] .... # echo 'sshd_enable="YES"' >> /etc/rc.conf .... Alternatively, use man:sysrc[8] to modify [.filename]#/etc/rc.conf#: [source,shell] .... # sysrc sshd_enable="YES" .... To start up local services, place shell scripts in the [.filename]#/usr/local/etc/rc.d# directory. These shell scripts should be set executable, the default file mode is `555`. [[adding-users]] === How do I add a user easily? Use the man:adduser[8] command, or the man:pw[8] command for more complicated situations. To remove the user, use the man:rmuser[8] command or, if necessary, man:pw[8]. [[root-not-found-cron-errors]] === Why do I keep getting messages like root: not found after editing /etc/crontab? This is normally caused by editing the system crontab. This is not the correct way to do things as the system crontab has a different format to the per-user crontabs. The system crontab has an extra field, specifying which user to run the command as. man:cron[8] assumes this user is the first word of the command to execute. Since no such command exists, this error message is displayed. To delete the extra, incorrect crontab: [source,shell] .... # crontab -r .... [[su-wheel-group]] === Why do I get the error, you are not in the correct group to su root when I try to su to root? This is a security feature. In order to `su` to `root`, or any other account with superuser privileges, the user account must be a member of the `wheel` group. If this feature were not there, anybody with an account on a system who also found out ``root``'s password would be able to gain superuser level access to the system. To allow someone to `su` to `root`, put them in the `wheel` group using `pw`: [source,shell] .... # pw groupmod wheel -m lisa .... The above example will add user `lisa` to the group `wheel`. [[rcconf-readonly]] === I made a mistake in rc.conf, or another startup file, and now I cannot edit it because the file system is read-only. What should I do? Restart the system using `boot -s` at the loader prompt to enter single-user mode. When prompted for a shell pathname, press kbd:[Enter] and run `mount -urw /` to re-mount the root file system in read/write mode. You may also need to run `mount -a -t ufs` to mount the file system where your favorite editor is defined. If that editor is on a network file system, either configure the network manually before mounting the network file systems, or use an editor which resides on a local file system, such as man:ed[1]. In order to use a full screen editor such as man:vi[1] or man:emacs[1], run `export TERM=xterm` so that these editors can load the correct data from the man:termcap[5] database. After performing these steps, edit [.filename]#/etc/rc.conf# to fix the syntax error. The error message displayed immediately after the kernel boot messages should indicate the number of the line in the file which is at fault. [[printer-setup]] === Why am I having trouble setting up my printer? See the extref:{handbook}[Handbook entry on printing, printing] for troubleshooting tips. [[keyboard-mappings]] === How can I correct the keyboard mappings for my system? Refer to the Handbook section on extref:{handbook}[using localization, using-localization], specifically the section on extref:{handbook}[console setup, setting-console]. [[user-quotas]] === Why can I not get user quotas to work properly? . It is possible that the kernel is not configured to use quotas. In this case, add the following line to the kernel configuration file and recompile the kernel: + [.programlisting] .... options QUOTA .... + Refer to the extref:{handbook}[Handbook entry on quotas, quotas] for full details. . Do not turn on quotas on [.filename]#/#. . Put the quota file on the file system that the quotas are to be enforced on: + [.informaltable] [cols="1,1", frame="none", options="header"] |=== | File System | Quota file |[.filename]#/usr# |[.filename]#/usr/admin/quotas# |[.filename]#/home# |[.filename]#/home/admin/quotas# |... |... |=== [[sysv-ipc]] === Does FreeBSD support System V IPC primitives? Yes, FreeBSD supports System V-style IPC, including shared memory, messages and semaphores, in the [.filename]#GENERIC# kernel. With a custom kernel, support may be loaded with the [.filename]#sysvshm.ko#, [.filename]#sysvsem.ko# and [.filename]#sysvmsg.ko# kernel modules, or enabled in the custom kernel by adding the following lines to the kernel configuration file: [.programlisting] .... options SYSVSHM # enable shared memory options SYSVSEM # enable for semaphores options SYSVMSG # enable for messaging .... Recompile and install the kernel. [[sendmail-alternative]] === What other mail-server software can I use instead of Sendmail? The http://www.sendmail.org/[Sendmail] server is the default mail-server software for FreeBSD, but it can be replaced with another MTA installed from the Ports Collection. Available ports include package:mail/exim[], package:mail/postfix[], and package:mail/qmail[]. Search the mailing lists for discussions regarding the advantages and disadvantages of the available MTAs. [[forgot-root-pw]] === I have forgotten the root password! What do I do? Do not panic! Restart the system, type `boot -s` at the `Boot:` prompt to enter single-user mode. At the question about the shell to use, hit kbd:[Enter] which will display a # prompt. Enter `mount -urw /` to remount the root file system read/write, then run `mount -a` to remount all the file systems. Run `passwd root` to change the `root` password then run man:exit[1] to continue booting. [NOTE] ==== If you are still prompted to give the `root` password when entering the single-user mode, it means that the console has been marked as `insecure` in [.filename]#/etc/ttys#. In this case, it will be required to boot from a FreeBSD installation disk, choose the [.guimenuitem]#Live CD# or [.guimenuitem]#Shell# at the beginning of the install process and issue the commands mentioned above. Mount the specific partition in this case and then chroot to it. For example, replace `mount -urw /` with `mount /dev/ada0p1 /mnt; chroot /mnt` for a system on _ada0p1_. ==== [NOTE] ==== If the root partition cannot be mounted from single-user mode, it is possible that the partitions are encrypted and it is impossible to mount them without the access keys. For more information see the section about encrypted disks in the FreeBSD extref:{handbook}[Handbook, disks-encrypting]. ==== [[CAD-reboot]] === How do I keep kbd:[Control] + kbd:[Alt] + kbd:[Delete] from rebooting the system? When using man:vt[4], the default console driver, this can be done by setting the following man:sysctl[8]: [source,shell] .... # sysctl kern.vt.kbd_reboot=0 .... [[dos-to-unix-txt]] === How do I reformat DOS text files to UNIX(R) ones? Use this man:perl[1] command: [source,shell] .... % perl -i.bak -npe 's/\r\n/\n/g' file(s) .... where _file(s)_ is one or more files to process. The modification is done in-place, with the original file stored with a [.filename]#.bak# extension. Alternatively, use man:tr[1]: [source,shell] .... % tr -d '\r' < dos-text-file > unix-file .... _dos-text-file_ is the file containing DOS text while _unix-file_ will contain the converted output. This can be quite a bit faster than using `perl`. Yet another way to reformat DOS text files is to use the package:converters/dosunix[] port from the Ports Collection. Consult its documentation about the details. [[reread-rc]] === How do I re-read [.filename]#/etc/rc.conf# and re-start [.filename]#/etc/rc# without a reboot? Go into single-user mode and then back to multi-user mode: [source,shell] .... # shutdown now # return # exit .... [[release-candidate]] === I tried to update my system to the latest _-STABLE_, but got _-BETAx_, _-RC_ or __-PRERELEASE__! What is going on? Short answer: it is just a name. _RC_ stands for "Release Candidate". It signifies that a release is imminent. In FreeBSD, _-PRERELEASE_ is typically synonymous with the code freeze before a release. (For some releases, the _-BETA_ label was used in the same way as _-PRERELEASE_.) Long answer: FreeBSD derives its releases from one of two places. Major, dot-zero, releases, such as 9.0-RELEASE are branched from the head of the development stream, commonly referred to as <>. Minor releases, such as 6.3-RELEASE or 5.2-RELEASE, have been snapshots of the active <> branch. Starting with 4.3-RELEASE, each release also now has its own branch which can be tracked by people requiring an extremely conservative rate of development (typically only security advisories). When a release is about to be made, the branch from which it will be derived from has to undergo a certain process. Part of this process is a code freeze. When a code freeze is initiated, the name of the branch is changed to reflect that it is about to become a release. For example, if the branch used to be called 6.2-STABLE, its name will be changed to 6.3-PRERELEASE to signify the code freeze and signify that extra pre-release testing should be happening. Bug fixes can still be committed to be part of the release. When the source code is in shape for the release the name will be changed to 6.3-RC to signify that a release is about to be made from it. Once in the RC stage, only the most critical bugs found can be fixed. Once the release (6.3-RELEASE in this example) and release branch have been made, the branch will be renamed to 6.3-STABLE. For more information on version numbers and the various Subversion branches, refer to the extref:{releng}[Release Engineering] article. [[kernel-chflag-failure]] === I tried to install a new kernel, and the man:chflags[1] failed. How do I get around this? Short answer: the security level is greater than 0. Reboot directly to single-user mode to install the kernel. Long answer: FreeBSD disallows changing system flags at security levels greater than 0. To check the current security level: [source,shell] .... # sysctl kern.securelevel .... The security level cannot be lowered in multi-user mode, so boot to single-user mode to install the kernel, or change the security level in [.filename]#/etc/rc.conf# then reboot. See the man:init[8] manual page for details on `securelevel`, and see [.filename]#/etc/defaults/rc.conf# and the man:rc.conf[5] manual page for more information on [.filename]#rc.conf#. [[kernel-securelevel-time]] === I cannot change the time on my system by more than one second! How do I get around this? Short answer: the system is at a security level greater than 1. Reboot directly to single-user mode to change the date. Long answer: FreeBSD disallows changing the time by more that one second at security levels greater than 1. To check the security level: [source,shell] .... # sysctl kern.securelevel .... The security level cannot be lowered in multi-user mode. Either boot to single-user mode to change the date or change the security level in [.filename]#/etc/rc.conf# and reboot. See the man:init[8] manual page for details on `securelevel`, and see [.filename]#/etc/defaults/rc.conf# and the man:rc.conf[5] manual page for more information on [.filename]#rc.conf#. [[statd-mem-leak]] === Why is rpc.statd using 256 MB of memory? No, there is no memory leak, and it is not using 256 MB of memory. For convenience, `rpc.statd` maps an obscene amount of memory into its address space. There is nothing terribly wrong with this from a technical standpoint; it just throws off things like man:top[1] and man:ps[1]. man:rpc.statd[8] maps its status file (resident on [.filename]#/var#) into its address space; to save worrying about remapping the status file later when it needs to grow, it maps the status file with a generous size. This is very evident from the source code, where one can see that the length argument to man:mmap[2] is `0x10000000`, or one sixteenth of the address space on an IA32, or exactly 256 MB. [[unsetting-schg]] === Why can I not unset the schg file flag? The system is running at securelevel greater than 0. Lower the securelevel and try again. For more information, see <> and the man:init[8] manual page. [[vnlru]] === What is vnlru? `vnlru` flushes and frees vnodes when the system hits the `kern.maxvnodes` limit. This kernel thread sits mostly idle, and only activates when there is a huge amount of RAM and users are accessing tens of thousands of tiny files. [[top-memory-states]] === What do the various memory states displayed by top mean? * `Active`: pages recently statistically used. * `Inactive`: pages recently statistically unused. * `Laundry`: pages recently statistically unused but known to be dirty, that is, whose contents needs to be paged out before they can be reused. * `Free`: pages without data content, which can be immediately reused. * `Wired`: pages that are fixed into memory, usually for kernel purposes, but also sometimes for special use in processes. Pages are most often written to disk (sort of a VM sync) when they are in the laundry state, but active or inactive pages can also be synced. This depends upon the CPU tracking of the modified bit being available, and in certain situations there can be an advantage for a block of VM pages to be synced, regardless of the queue they belong to. In most common cases, it is best to think of the laundry queue as a queue of relatively unused pages that might or might not be in the process of being written to disk. The inactive queue contains a mix of clean and dirty pages; clean pages near the head of the queue are reclaimed immediately to alleviate a free page shortage, and dirty pages are moved to the laundry queue for deferred processing. There are some other flags (e.g., busy flag or busy count) that might modify some of the described rules. [[free-memory-amount]] === How much free memory is available? There are a couple of kinds of "free memory". The most common is the amount of memory immediately available without reclaiming memory already in use. That is the size of the free pages queue plus some other reserved pages. This amount is exported by the `vm.stats.vm.v_free_count` man:sysctl[8], shown, for instance, by man:top[1]. Another kind of "free memory" is the total amount of virtual memory available to userland processes, which depends on the sum of swap space and usable memory. Other kinds of "free memory" descriptions are also possible, but it is relatively useless to define these, but rather it is important to make sure that the paging rate is kept low, and to avoid running out of swap space. [[var-empty]] === What is [.filename]#/var/empty#? [.filename]#/var/empty# is a directory that the man:sshd[8] program uses when performing privilege separation. The [.filename]#/var/empty# directory is empty, owned by `root` and has the `schg` flag set. This directory should not be deleted. [[newsyslog-expectations]] === I just changed [.filename]#/etc/newsyslog.conf#. How can I check if it does what I expect? To see what man:newsyslog[8] will do, use the following: [source,shell] .... % newsyslog -nrvv .... [[timezone]] === My time is wrong, how can I change the timezone? Use man:tzsetup[8]. [[X11]] == The X Window System and Virtual Consoles [[whatis-X]] === What is the X Window System? The X Window System (commonly `X11`) is the most widely available windowing system capable of running on UNIX(R) or UNIX(R) like systems, including FreeBSD. http://www.x.org/wiki/[The X.Org Foundation] administers the http://en.wikipedia.org/wiki/X_Window_System_core_protocol[X protocol standards], with the current reference implementation, version 11 release 7.7, so references are often shortened to `X11`. Many implementations are available for different architectures and operating systems. An implementation of the server-side code is properly known as an `X server`. [[running-X]] === I want to run Xorg, how do I go about it? To install Xorg do one of the following: Use the package:x11/xorg[] meta-port, which builds and installs every Xorg component. Use package:x11/xorg-minimal[], which builds and installs only the necessary Xorg components. Install Xorg from FreeBSD packages: [source,shell] .... # pkg install xorg .... After the installation of Xorg, follow the instructions from the extref:{handbook}[X11 Configuration, x-config] section of the FreeBSD Handbook. [[running-X-securelevels]] === I tried to run X, but I get a No devices detected. error when I type startx. What do I do now? The system is probably running at a raised `securelevel`. It is not possible to start X at a raised `securelevel` because X requires write access to man:io[4]. For more information, see at the man:init[8] manual page. There are two solutions to the problem: -set the `securelevel` back down to zero or run man:xdm[1] (or an alternative display manager) at boot time before the `securelevel` is raised. +set the `securelevel` back down to zero or run man:xdm[8] (or an alternative display manager) at boot time before the `securelevel` is raised. -See <> for more information about running man:xdm[1] at boot time. +See <> for more information about running man:xdm[8] at boot time. [[x-and-moused]] === Why does my mouse not work with X? When using man:vt[4], the default console driver, FreeBSD can be configured to support a mouse pointer on each virtual screen. To avoid conflicting with X, man:vt[4] supports a virtual device called [.filename]#/dev/sysmouse#. All mouse events received from the real mouse device are written to the man:sysmouse[4] device via man:moused[8]. To use the mouse on one or more virtual consoles, _and_ use X, see <> and set up man:moused[8]. Then edit [.filename]#/etc/X11/xorg.conf# and make sure the following lines exist: [.programlisting] .... Section "InputDevice" Option "Protocol" "SysMouse" Option "Device" "/dev/sysmouse" ..... .... Starting with Xorg version 7.4, the `InputDevice` sections in [.filename]#xorg.conf# are ignored in favor of autodetected devices. To restore the old behavior, add the following line to the `ServerLayout` or `ServerFlags` section: [.programlisting] .... Option "AutoAddDevices" "false" .... Some people prefer to use [.filename]#/dev/mouse# under X. To make this work, [.filename]#/dev/mouse# should be linked to [.filename]#/dev/sysmouse# (see man:sysmouse[4]) by adding the following line to [.filename]#/etc/devfs.conf# (see man:devfs.conf[5]): [.programlisting] .... link sysmouse mouse .... This link can be created by restarting man:devfs[5] with the following command (as `root`): [source,shell] .... # service devfs restart .... [[x-and-wheel]] === My mouse has a fancy wheel. Can I use it in X? Yes, if X is configured for a 5 button mouse. To do this, add the lines `Buttons 5` and `ZAxisMapping 4 5` to the "InputDevice" section of [.filename]#/etc/X11/xorg.conf#, as seen in this example: [.programlisting] .... Section "InputDevice" Identifier "Mouse1" Driver "mouse" Option "Protocol" "auto" Option "Device" "/dev/sysmouse" Option "Buttons" "5" Option "ZAxisMapping" "4 5" EndSection .... The mouse can be enabled in Emacs by adding these lines to [.filename]#~/.emacs#: [.programlisting] .... ;; wheel mouse (global-set-key [mouse-4] 'scroll-down) (global-set-key [mouse-5] 'scroll-up) .... [[x-and-synaptic]] === My laptop has a Synaptics touchpad. Can I use it in X? Yes, after configuring a few things to make it work. In order to use the Xorg synaptics driver, first remove `moused_enable` from [.filename]#rc.conf#. To enable synaptics, add the following line to [.filename]#/boot/loader.conf#: [.programlisting] .... hw.psm.synaptics_support="1" .... Add the following to [.filename]#/etc/X11/xorg.conf#: [.programlisting] .... Section "InputDevice" Identifier "Touchpad0" Driver "synaptics" Option "Protocol" "psm" Option "Device" "/dev/psm0" EndSection .... And be sure to add the following into the "ServerLayout" section: [.programlisting] .... InputDevice "Touchpad0" "SendCoreEvents" .... [[no-remote-x11]] === How do I use remote X displays? For security reasons, the default setting is to not allow a machine to remotely open a window. To enable this feature, start X with the optional `-listen_tcp` argument: [source,shell] .... % startx -listen_tcp .... [[virtual-console]] === What is a virtual console and how do I make more? Virtual consoles provide several simultaneous sessions on the same machine without doing anything complicated like setting up a network or running X. When the system starts, it will display a login prompt on the monitor after displaying all the boot messages. Type in your login name and password to start working on the first virtual console. To start another session, perhaps to look at documentation for a program or to read mail while waiting for an FTP transfer to finish, hold down kbd:[Alt] and press kbd:[F2]. This will display the login prompt for the second virtual console. To go back to the original session, press kbd:[Alt+F1]. The default FreeBSD installation has eight virtual consoles enabled. kbd:[Alt+F1], kbd:[Alt+F2], kbd:[Alt+F3], and so on will switch between these virtual consoles. To enable more of virtual consoles, edit [.filename]#/etc/ttys# (see man:ttys[5]) and add entries for [.filename]#ttyv8# to [.filename]#ttyvc#, after the comment on "Virtual terminals": [.programlisting] .... # Edit the existing entry for ttyv8 in /etc/ttys and change # "off" to "on". ttyv8 "/usr/libexec/getty Pc" xterm on secure ttyv9 "/usr/libexec/getty Pc" xterm on secure ttyva "/usr/libexec/getty Pc" xterm on secure ttyvb "/usr/libexec/getty Pc" xterm on secure .... The more virtual terminals, the more resources that are used. This can be problematic on systems with 8 MB RAM or less. Consider changing `secure` to `insecure`. [IMPORTANT] ==== In order to run an X server, at least one virtual terminal must be left to `off` for it to use. This means that only eleven of the Alt-function keys can be used as virtual consoles so that one is left for the X server. ==== For example, to run X and eleven virtual consoles, the setting for virtual terminal 12 should be: [.programlisting] .... ttyvb "/usr/libexec/getty Pc" xterm off secure .... The easiest way to activate the virtual consoles is to reboot. [[vty-from-x]] === How do I access the virtual consoles from X? Use kbd:[Ctrl+Alt+Fn] to switch back to a virtual console. Press kbd:[Ctrl+Alt+F1] to return to the first virtual console. Once at a text console, use kbd:[Alt+Fn] to move between them. To return to the X session, switch to the virtual console running X. If X was started from the command line using `startx`, the X session will attach to the next unused virtual console, not the text console from which it was invoked. For eight active virtual terminals, X will run on the ninth, so use kbd:[Alt+F9]. [[xdm-boot]] === How do I start XDM on boot? -There are two schools of thought on how to start man:xdm[1]. +There are two schools of thought on how to start man:xdm[8]. One school starts `xdm` from [.filename]#/etc/ttys# (see man:ttys[5]) using the supplied example, while the other sets `xdm_enable=yes` in [.filename]#/etc/rc.conf#. Both are equally valid, and one may work in situations where the other does not. In both cases the result is the same: X will pop up a graphical login prompt. The man:ttys[5] method has the advantage of documenting which vty X will start on and passing the responsibility of restarting the X server on logout to man:init[8]. The man:rc[8] method makes it easy to `kill xdm` if there is a problem starting the X server. -When using the man:rc[8] method, `xdm_tty` (default `ttyv8`) can be set in [.filename]#/etc/rc.conf# to choose which vty man:xdm[1] opens on. +When using the man:rc[8] method, `xdm_tty` (default `ttyv8`) can be set in [.filename]#/etc/rc.conf# to choose which vty man:xdm[8] opens on. [[xconsole-failure]] === Why do I get Couldn't open console when I run xconsole? When X is started with `startx`, the permissions on [.filename]#/dev/console# will _not_ get changed, resulting in things like `xterm -C` and `xconsole` not working. This is because of the way console permissions are set by default. On a multi-user system, one does not necessarily want just any user to be able to write on the system console. For users who are logging directly onto a machine with a VTY, the man:fbtab[5] file exists to solve such problems. In a nutshell, make sure an uncommented line of the form is in [.filename]#/etc/fbtab# (see man:fbtab[5]): [.programlisting] .... /dev/ttyv0 0600 /dev/console .... It will ensure that whomever logs in on [.filename]#/dev/ttyv0# will own the console. [[ps2-x]] === Why does my PS/2 mouse misbehave under X? The mouse and the mouse driver may have become out of synchronization. In rare cases, the driver may also erroneously report synchronization errors: [.programlisting] .... psmintr: out of sync (xxxx != yyyy) .... If this happens, disable the synchronization check code by setting the driver flags for the PS/2 mouse driver to `0x100`. This can be easiest achieved by adding `hint.psm.0.flags="0x100"` to [.filename]#/boot/loader.conf# and rebooting. [[mouse-button-reverse]] === How do I reverse the mouse buttons? Type `xmodmap -e "pointer = 3 2 1"`. Add this command to [.filename]#~/.xinitrc# or [.filename]#~/.xsession# to make it happen automatically. [[install-splash]] === How do I install a splash screen and where do I find them? The detailed answer for this question can be found in the extref:{handbook}[Boot Time Splash Screens, boot-splash] section of the FreeBSD Handbook. [[windows-keys]] === Can I use the kbd:[Windows] keys on my keyboard in X? Yes. Use man:xmodmap[1] to define which functions the keys should perform. Assuming all Windows keyboards are standard, the keycodes for these three keys are the following: * 115 - kbd:[Windows] key, between the left-hand kbd:[Ctrl] and kbd:[Alt] keys * 116 - kbd:[Windows] key, to the right of kbd:[AltGr] * 117 - kbd:[Menu], to the left of the right-hand kbd:[Ctrl] To have the left kbd:[Windows] key print a comma, try this. [source,shell] .... # xmodmap -e "keycode 115 = comma" .... To have the kbd:[Windows] key-mappings enabled automatically every time X is started, either put the `xmodmap` commands in [.filename]#~/.xinitrc# or, preferably, create a [.filename]#~/.xmodmaprc# and include the `xmodmap` options, one per line, then add the following line to [.filename]#~/.xinitrc#: [.programlisting] .... xmodmap $HOME/.xmodmaprc .... For example, to map the 3 keys to be kbd:[F13], kbd:[F14], and kbd:[F15], respectively. This would make it easy to map them to useful functions within applications or the window manager. To do this, put the following in [.filename]#~/.xmodmaprc#. [.programlisting] .... keycode 115 = F13 keycode 116 = F14 keycode 117 = F15 .... For the package:x11-wm/fvwm2[] desktop manager, one could map the keys so that kbd:[F13] iconifies or de-iconifies the window the cursor is in, kbd:[F14] brings the window the cursor is in to the front or, if it is already at the front, pushes it to the back, and kbd:[F15] pops up the main Workplace menu even if the cursor is not on the desktop, which is useful when no part of the desktop is visible. The following entries in [.filename]#~/.fvwmrc# implement the aforementioned setup: [.programlisting] .... Key F13 FTIWS A Iconify Key F14 FTIWS A RaiseLower Key F15 A A Menu Workplace Nop .... [[x-3d-acceleration]] === How can I get 3D hardware acceleration for OpenGL(R)? The availability of 3D acceleration depends on the version of Xorg and the type of video chip. For an nVidia chip, use the binary drivers provided for FreeBSD by installing one of the following ports: The latest versions of nVidia cards are supported by the package:x11/nvidia-driver[] port. Older drivers are available as: * package:x11/nvidia-driver-390[] * package:x11/nvidia-driver-340[] * package:x11/nvidia-driver-304[] nVidia provides detailed information on which card is supported by which driver on their web site: http://www.nvidia.com/object/IO_32667.html[http://www.nvidia.com/object/IO_32667.html]. For Matrox G200/G400, check the package:x11-drivers/xf86-video-mga[] port. For ATI Rage 128 and Radeon see man:ati[4], man:r128[4] and man:radeon[4]. [[networking]] == Networking [[diskless-booting]] === Where can I get information on diskless booting? "Diskless booting" means that the FreeBSD box is booted over a network, and reads the necessary files from a server instead of its hard disk. For full details, see extref:{handbook}[the Handbook entry on diskless booting, network-diskless]. [[router]] === Can a FreeBSD box be used as a dedicated network router? Yes. Refer to the Handbook entry on extref:{handbook}[advanced networking, advanced-networking], specifically the section on extref:{handbook}[routing and gateways, network-routing]. [[natd]] === Does FreeBSD support NAT or Masquerading? Yes. For instructions on how to use NAT over a PPP connection, see the extref:{handbook}[Handbook entry on PPP, userppp]. To use NAT over some other sort of network connection, look at the extref:{handbook}[natd, network-natd] section of the Handbook. [[ethernet-aliases]] === How can I set up Ethernet aliases? If the alias is on the same subnet as an address already configured on the interface, add `netmask 0xffffffff` to this command: [source,shell] .... # ifconfig ed0 alias 192.0.2.2 netmask 0xffffffff .... Otherwise, specify the network address and netmask as usual: [source,shell] .... # ifconfig ed0 alias 172.16.141.5 netmask 0xffffff00 .... More information can be found in the FreeBSD extref:{handbook}[Handbook, configtuning-virtual-hosts]. [[nfs-linux]] === Why can I not NFS-mount from a Linux(R) box? Some versions of the Linux(R) NFS code only accept mount requests from a privileged port; try to issue the following command: [source,shell] .... # mount -o -P linuxbox:/blah /mnt .... [[exports-errors]] === Why does mountd keep telling me it can't change attributes and that I have a bad exports list on my FreeBSD NFS server? The most frequent problem is not understanding the correct format of [.filename]#/etc/exports#. Review man:exports[5] and the extref:{handbook}[NFS, network-nfs] entry in the Handbook, especially the section on extref:{handbook}[configuring NFS, configuring-nfs]. [[ip-multicast]] === How do I enable IP multicast support? Install the package:net/mrouted[] package or port and add `mrouted_enable="YES"` to [.filename]#/etc/rc.conf# start this service at boot time. [[fqdn-hosts]] === Why do I have to use the FQDN for hosts on my site? See the answer in the FreeBSD extref:{handbook}[Handbook, mail-trouble]. [[network-permission-denied]] === Why do I get an error, Permission denied, for all networking operations? If the kernel is compiled with the `IPFIREWALL` option, be aware that the default policy is to deny all packets that are not explicitly allowed. If the firewall is unintentionally misconfigured, restore network operability by typing the following as `root`: [source,shell] .... # ipfw add 65534 allow all from any to any .... Consider setting `firewall_type="open"` in [.filename]#/etc/rc.conf#. For further information on configuring this firewall, see the extref:{handbook}[Handbook chapter, firewalls-ipfw]. [[ipfw-fwd]] === Why is my `ipfw` “fwd” rule to redirect a service to another machine not working? Possibly because network address translation (NAT) is needed instead of just forwarding packets. A "fwd" rule only forwards packets, it does not actually change the data inside the packet. Consider this rule: [source,shell] .... 01000 fwd 10.0.0.1 from any to foo 21 .... When a packet with a destination address of _foo_ arrives at the machine with this rule, the packet is forwarded to _10.0.0.1_, but it still has the destination address of _foo_. The destination address of the packet is not changed to _10.0.0.1_. Most machines would probably drop a packet that they receive with a destination address that is not their own. Therefore, using a "fwd" rule does not often work the way the user expects. This behavior is a feature and not a bug. See the <>, the man:natd[8] manual, or one of the several port redirecting utilities in the link:https://www.FreeBSD.org/ports/[Ports Collection] for a correct way to do this. [[service-redirect]] === How can I redirect service requests from one machine to another? FTP and other service requests can be redirected with the package:sysutils/socket[] package or port. Replace the entry for the service in [.filename]#/etc/inetd.conf# to call `socket`, as seen in this example for ftpd: [.programlisting] .... ftp stream tcp nowait nobody /usr/local/bin/socket socket ftp.example.com ftp .... where _ftp.example.com_ and _ftp_ are the host and port to redirect to, respectively. [[bandwidth-mgr-tool]] === Where can I get a bandwidth management tool? There are three bandwidth management tools available for FreeBSD. man:dummynet[4] is integrated into FreeBSD as part of man:ipfw[4]. http://www.sonycsl.co.jp/person/kjc/programs.html[ALTQ] has been integrated into FreeBSD as part of man:pf[4]. Bandwidth Manager from http://www.etinc.com/[Emerging Technologies] is a commercial product. [[bpf-not-configured]] === Why do I get /dev/bpf0: device not configured? The running application requires the Berkeley Packet Filter (man:bpf[4]), but it was removed from a custom kernel. Add this to the kernel config file and build a new kernel: [.programlisting] .... device bpf # Berkeley Packet Filter .... [[mount-smb-share]] === How do I mount a disk from a Windows(R) machine that is on my network, like smbmount in Linux(R)? Use the SMBFS toolset. It includes a set of kernel modifications and a set of userland programs. The programs and information are available as man:mount_smbfs[8] in the base system. [[icmp-response-bw-limit]] === What are these messages about: Limiting icmp/open port/closed port response in my log files? This kernel message indicates that some activity is provoking it to send a large amount of ICMP or TCP reset (RST) responses. ICMP responses are often generated as a result of attempted connections to unused UDP ports. TCP resets are generated as a result of attempted connections to unopened TCP ports. Among others, these are the kinds of activities which may cause these messages: * Brute-force denial of service (DoS) attacks (as opposed to single-packet attacks which exploit a specific vulnerability). * Port scans which attempt to connect to a large number of ports (as opposed to only trying a few well-known ports). The first number in the message indicates how many packets the kernel would have sent if the limit was not in place, and the second indicates the limit. This limit is controlled using `net.inet.icmp.icmplim`. This example sets the limit to `300` packets per second: [source,shell] .... # sysctl net.inet.icmp.icmplim=300 .... To disable these messages without disabling response limiting, use `net.inet.icmp.icmplim_output` to disable the output: [source,shell] .... # sysctl net.inet.icmp.icmplim_output=0 .... Finally, to disable response limiting completely, set `net.inet.icmp.icmplim` to `0`. Disabling response limiting is discouraged for the reasons listed above. [[unknown-hw-addr-format]] === What are these arp: unknown hardware address format error messages? This means that some device on the local Ethernet is using a MAC address in a format that FreeBSD does not recognize. This is probably caused by someone experimenting with an Ethernet card somewhere else on the network. This is most commonly seen on cable modem networks. It is harmless, and should not affect the performance of the FreeBSD system. [[arp-wrong-iface]] === Why do I keep seeing messages like: 192.168.0.10 is on fxp1 but got reply from 00:15:17:67:cf:82 on rl0, and how do I disable it? A packet is coming from outside the network unexpectedly. To disable them, set `net.link.ether.inet.log_arp_wrong_iface` to `0`. [[ipv6-only]] === How do I compile an IPv6 only kernel? Configure your kernel with these settings: [source,shell] .... include GENERIC ident GENERIC-IPV6ONLY makeoptions MKMODULESENV+="WITHOUT_INET_SUPPORT=" nooptions INET nodevice gre .... [[security]] == Security [[sandbox]] === What is a sandbox? "Sandbox" is a security term. It can mean two things: * A process which is placed inside a set of virtual walls that are designed to prevent someone who breaks into the process from being able to break into the wider system. + The process is only able to run inside the walls. Since nothing the process does in regards to executing code is supposed to be able to breach the walls, a detailed audit of its code is not needed in order to be able to say certain things about its security. + The walls might be a user ID, for example. This is the definition used in the man:security[7] and man:named[8] man pages. + Take the `ntalk` service, for example (see man:inetd[8]). This service used to run as user ID `root`. Now it runs as user ID `tty`. The `tty` user is a sandbox designed to make it more difficult for someone who has successfully hacked into the system via `ntalk` from being able to hack beyond that user ID. * A process which is placed inside a simulation of the machine. It means that someone who is able to break into the process may believe that he can break into the wider machine but is, in fact, only breaking into a simulation of that machine and not modifying any real data. + The most common way to accomplish this is to build a simulated environment in a subdirectory and then run the processes in that directory chrooted so that [.filename]#/# for that process is this directory, not the real [.filename]#/# of the system). + Another common use is to mount an underlying file system read-only and then create a file system layer on top of it that gives a process a seemingly writeable view into that file system. The process may believe it is able to write to those files, but only the process sees the effects - other processes in the system do not, necessarily. + An attempt is made to make this sort of sandbox so transparent that the user (or hacker) does not realize that he is sitting in it. UNIX(R) implements two core sandboxes. One is at the process level, and one is at the userid level. Every UNIX(R) process is completely firewalled off from every other UNIX(R) process. One process cannot modify the address space of another. A UNIX(R) process is owned by a particular userid. If the user ID is not the `root` user, it serves to firewall the process off from processes owned by other users. The user ID is also used to firewall off on-disk data. [[securelevel]] === What is securelevel? `securelevel` is a security mechanism implemented in the kernel. When the securelevel is positive, the kernel restricts certain tasks; not even the superuser (`root`) is allowed to do them. The securelevel mechanism limits the ability to: * Unset certain file flags, such as `schg` (the system immutable flag). * Write to kernel memory via [.filename]#/dev/mem# and [.filename]#/dev/kmem#. * Load kernel modules. * Alter firewall rules. To check the status of the securelevel on a running system: [source,shell] .... # sysctl -n kern.securelevel .... The output contains the current value of the securelevel. If it is greater than 0, at least some of the securelevel's protections are enabled. The securelevel of a running system cannot be lowered as this would defeat its purpose. If a task requires that the securelevel be non-positive, change the `kern_securelevel` and `kern_securelevel_enable` variables in [.filename]#/etc/rc.conf# and reboot. For more information on securelevel and the specific things all the levels do, consult man:init[8]. [WARNING] ==== Securelevel is not a silver bullet; it has many known deficiencies. More often than not, it provides a false sense of security. One of its biggest problems is that in order for it to be at all effective, all files used in the boot process up until the securelevel is set must be protected. If an attacker can get the system to execute their code prior to the securelevel being set (which happens quite late in the boot process since some things the system must do at start-up cannot be done at an elevated securelevel), its protections are invalidated. While this task of protecting all files used in the boot process is not technically impossible, if it is achieved, system maintenance will become a nightmare since one would have to take the system down, at least to single-user mode, to modify a configuration file. This point and others are often discussed on the mailing lists, particularly the {freebsd-security}. Search the archives link:https://www.FreeBSD.org/search/[here] for an extensive discussion. A more fine-grained mechanism is preferred. ==== [[toor-account]] === What is this UID 0 toor account? Have I been compromised? Do not worry. `toor` is an "alternative" superuser account, where toor is root spelled backwards. It is intended to be used with a non-standard shell so the default shell for `root` does not need to change. This is important as shells which are not part of the base distribution, but are instead installed from ports or packages, are installed in [.filename]#/usr/local/bin# which, by default, resides on a different file system. If ``root``'s shell is located in [.filename]#/usr/local/bin# and the file system containing [.filename]#/usr/local/bin#) is not mounted, `root` will not be able to log in to fix a problem and will have to reboot into single-user mode in order to enter the path to a shell. Some people use `toor` for day-to-day `root` tasks with a non-standard shell, leaving `root`, with a standard shell, for single-user mode or emergencies. By default, a user cannot log in using `toor` as it does not have a password, so log in as `root` and set a password for `toor` before using it to login. [[serial]] == Serial Communications This section answers common questions about serial communications with FreeBSD. [[serial-console-prompt]] === How do I get the boot: prompt to show on the serial console? See extref:{handbook}[this section of the Handbook, serialconsole-setup]. [[found-serial]] === How do I tell if FreeBSD found my serial ports or modem cards? As the FreeBSD kernel boots, it will probe for the serial ports for which the kernel is configured. Either watch the boot messages closely or run this command after the system is up and running: [source,shell] .... % grep -E '^(sio|uart)[0-9]' < /var/run/dmesg.boot uart0: <16550 or compatible> port 0x3f8-0x3ff irq 4 flags 0x10 on acpi0 uart0: console (115200,n,8,1) uart1: <16550 or compatible> port 0x2f8-2x3ff irq 3 on acpi0 .... This example shows two serial ports. The first is on IRQ4, port address `0x3f8`, and has a 16550-type UART chip. The second uses the same kind of chip but is on IRQ3 and is at port address `0x2f8`. Internal modem cards are treated just like serial ports, except that they always have a modem attached to the port. The [.filename]#GENERIC# kernel includes support for two serial ports using the same IRQ and port address settings in the above example. If these settings are not right for the system, or if there are more modem cards or serial ports than the kernel is configured for, reconfigure using the instructions in <> for more details. [[access-serial-ports]] === How do I access the serial ports on FreeBSD? (x86-specific) The third serial port, [.filename]#sio2#, or [.filename]#COM3#, is on [.filename]#/dev/cuad2# for dial-out devices, and on [.filename]#/dev/ttyd2# for dial-in devices. What is the difference between these two classes of devices? When opening [.filename]#/dev/ttydX# in blocking mode, a process will wait for the corresponding [.filename]#cuadX# device to become inactive, and then wait for the carrier detect line to go active. When the [.filename]#cuadX# device is opened, it makes sure the serial port is not already in use by the [.filename]#ttydX# device. If the port is available, it steals it from the [.filename]#ttydX# device. Also, the [.filename]#cuadX# device does not care about carrier detect. With this scheme and an auto-answer modem, remote users can log in and local users can still dial out with the same modem and the system will take care of all the conflicts. [[enable-multiport-serial]] === How do I enable support for a multi-port serial card? The section on kernel configuration provides information about configuring the kernel. For a multi-port serial card, place an man:sio[4] line for each serial port on the card in the man:device.hints[5] file. But place the IRQ specifiers on only one of the entries. All of the ports on the card should share one IRQ. For consistency, use the last serial port to specify the IRQ. Also, specify the following option in the kernel configuration file: [.programlisting] .... options COM_MULTIPORT .... The following [.filename]#/boot/device.hints# example is for an AST 4-port serial card on IRQ 12: [.programlisting] .... hint.sio.4.at="isa" hint.sio.4.port="0x2a0" hint.sio.4.flags="0x701" hint.sio.5.at="isa" hint.sio.5.port="0x2a8" hint.sio.5.flags="0x701" hint.sio.6.at="isa" hint.sio.6.port="0x2b0" hint.sio.6.flags="0x701" hint.sio.7.at="isa" hint.sio.7.port="0x2b8" hint.sio.7.flags="0x701" hint.sio.7.irq="12" .... The flags indicate that the master port has minor number `7` (`0x700`), and all the ports share an IRQ (`0x001`). [[default-serial-params]] === Can I set the default serial parameters for a port? See the extref:{handbook}serialcomms[Serial Communications, serial-hw-config] section in the FreeBSD Handbook. [[cannot-tip]] === Why can I not run tip or cu? The built-in man:tip[1] and man:cu[1] utilities can only access the [.filename]#/var/spool/lock# directory via user `uucp` and group `dialer`. Use the `dialer` group to control who has access to the modem or remote systems by adding user accounts to `dialer`. Alternatively, everyone can be configured to run man:tip[1] and man:cu[1] by typing: [source,shell] .... # chmod 4511 /usr/bin/cu # chmod 4511 /usr/bin/tip .... [[misc]] == Miscellaneous Questions [[more-swap]] === FreeBSD uses a lot of swap space even when the computer has free memory left. Why? FreeBSD will proactively move entirely idle, unused pages of main memory into swap in order to make more main memory available for active use. This heavy use of swap is balanced by using the extra free memory for caching. Note that while FreeBSD is proactive in this regard, it does not arbitrarily decide to swap pages when the system is truly idle. Thus, the system will not be all paged out after leaving it idle overnight. [[top-freemem]] === Why does top show very little free memory even when I have very few programs running? The simple answer is that free memory is wasted memory. Any memory that programs do not actively allocate is used within the FreeBSD kernel as disk cache. The values shown by man:top[1] labeled as `Inact` and `Laundry` are cached data at different aging levels. This cached data means the system does not have to access a slow disk again for data it has accessed recently, thus increasing overall performance. In general, a low value shown for `Free` memory in man:top[1] is good, provided it is not _very_ low. [[chmod-symlinks]] === Why will `chmod` not change the permissions on symlinks? Symlinks do not have permissions, and by default, man:chmod[1] will follow symlinks to change the permissions on the source file, if possible. For the file, [.filename]#foo# with a symlink named [.filename]#bar#, this command will always succeed. [source,shell] .... % chmod g-w bar .... However, the permissions on [.filename]#bar# will not have changed. When changing modes of the file hierarchies rooted in the files instead of the files themselves, use either `-H` or `-L` together with `-R` to make this work. See man:chmod[1] and man:symlink[7] for more information. [WARNING] ==== `-R` does a _recursive_ man:chmod[1]. Be careful about specifying directories or symlinks to directories to man:chmod[1]. To change the permissions of a directory referenced by a symlink, use man:chmod[1] without any options and follow the symlink with a trailing slash ([.filename]#/#). For example, if [.filename]#foo# is a symlink to directory [.filename]#bar#, to change the permissions of [.filename]#foo# (actually [.filename]#bar#), do something like: [source,shell] .... % chmod 555 foo/ .... With the trailing slash, man:chmod[1] will follow the symlink, [.filename]#foo#, to change the permissions of the directory, [.filename]#bar#. ==== [[dos-binaries]] === Can I run DOS binaries under FreeBSD? Yes. A DOS emulation program, package:emulators/doscmd[], is available in the FreeBSD Ports Collection. If doscmd will not suffice, package:emulators/pcemu[] emulates an 8088 and enough BIOS services to run many DOS text-mode applications. It requires the X Window System. The Ports Collection also has package:emulators/dosbox[]. The main focus of this application is emulating old DOS games using the local file system for files. [[translation]] === What do I need to do to translate a FreeBSD document into my native language? See the extref:{fdp-primer}[Translation FAQ, translations] in the FreeBSD Documentation Project Primer. [[freebsd-mail-bounces]] === Why does my email to any address at FreeBSD.org bounce? The `FreeBSD.org` mail system implements some Postfix checks on incoming mail and rejects mail that is either from misconfigured relays or otherwise appears likely to be spam. Some of the specific requirements are: * The IP address of the SMTP client must "reverse-resolve" to a forward confirmed hostname. * The fully-qualified hostname given in the SMTP conversation (either HELO or EHLO) must resolve to the IP address of the client. Other advice to help mail reach its destination include: * Mail should be sent in plain text, and messages sent to mailing lists should generally be no more than 200KB in length. * Avoid excessive cross posting. Choose _one_ mailing list which seems most relevant and send it there. If you still have trouble with email infrastructure at `FreeBSD.org`, send a note with the details to mailto:postmaster@freebsd.org[postmaster@freebsd.org]; Include a date/time interval so that logs may be reviewed - and note that we only keep one week's worth of mail logs. (Be sure to specify the time zone or offset from UTC.) [[free-account]] === Where can I find a free FreeBSD account? While FreeBSD does not provide open access to any of their servers, others do provide open access UNIX(R) systems. The charge varies and limited services may be available. http://www.arbornet.org/[Arbornet, Inc], also known as _M-Net_, has been providing open access to UNIX(R) systems since 1983. Starting on an Altos running System III, the site switched to BSD/OS in 1991. In June of 2000, the site switched again to FreeBSD. _M-Net_ can be accessed via telnet and SSH and provides basic access to the entire FreeBSD software suite. However, network access is limited to members and patrons who donate to the system, which is run as a non-profit organization. _M-Net_ also provides an bulletin board system and interactive chat. [[daemon-name]] === What is the cute little red guy's name? He does not have one, and is just called "the BSD daemon". If you insist upon using a name, call him "beastie". Note that "beastie" is pronounced "BSD". More about the BSD daemon is available on his http://www.mckusick.com/beastie/index.html[home page]. [[use-beastie]] === Can I use the BSD daemon image? Perhaps. The BSD daemon is copyrighted by Marshall Kirk McKusick. Check his http://www.mckusick.com/beastie/mainpage/copyright.html[Statement on the Use of the BSD Daemon Figure] for detailed usage terms. In summary, the image can be used in a tasteful manner, for personal use, so long as appropriate credit is given. Before using the logo commercially, contact {mckusick} for permission. More details are available on the http://www.mckusick.com/beastie/index.html[BSD Daemon's home page]. [[daemon-images]] === Do you have any BSD daemon images I could use? Xfig and eps drawings are available under [.filename]#/usr/share/examples/BSD_daemon/#. [[glossary]] === I have seen an acronym or other term on the mailing lists and I do not understand what it means. Where should I look? Refer to the extref:{handbook}[FreeBSD Glossary, freebsd-glossary]. [[bikeshed-painting]] === Why should I care what color the bikeshed is? The really, really short answer is that you should not. The somewhat longer answer is that just because you are capable of building a bikeshed does not mean you should stop others from building one just because you do not like the color they plan to paint it. This is a metaphor indicating that you need not argue about every little feature just because you know enough to do so. Some people have commented that the amount of noise generated by a change is inversely proportional to the complexity of the change. The longer and more complete answer is that after a very long argument about whether man:sleep[1] should take fractional second arguments, {phk} posted a long message entitled link:http://www.bikeshed.com[A bike shed (any color will do) on greener grass...]. The appropriate portions of that message are quoted below. **** “What is it about this bike shed?” Some of you have asked me. It is a long story, or rather it is an old story, but it is quite short actually. C. Northcote Parkinson wrote a book in the early 1960s, called “Parkinson's Law”, which contains a lot of insight into the dynamics of management. [snip a bit of commentary on the book] In the specific example involving the bike shed, the other vital component is an atomic power-plant, I guess that illustrates the age of the book. Parkinson shows how you can go into the board of directors and get approval for building a multi-million or even billion dollar atomic power plant, but if you want to build a bike shed you will be tangled up in endless discussions. Parkinson explains that this is because an atomic plant is so vast, so expensive and so complicated that people cannot grasp it, and rather than try, they fall back on the assumption that somebody else checked all the details before it got this far. Richard P. Feynmann gives a couple of interesting, and very much to the point, examples relating to Los Alamos in his books. A bike shed on the other hand. Anyone can build one of those over a weekend, and still have time to watch the game on TV. So no matter how well prepared, no matter how reasonable you are with your proposal, somebody will seize the chance to show that he is doing his job, that he is paying attention, that he is here. In Denmark we call it “setting your fingerprint”. It is about personal pride and prestige, it is about being able to point somewhere and say “There! I did that.” It is a strong trait in politicians, but present in most people given the chance. Just think about footsteps in wet cement. --Poul-Henning Kamp on freebsd-hackers, October 2, 1999 **** [[funnies]] == The FreeBSD Funnies [[very-very-cool]] === How cool is FreeBSD? _Q._ Has anyone done any temperature testing while running FreeBSD? I know Linux(R) runs cooler than DOS, but have never seen a mention of FreeBSD. It seems to run really hot. _A._ No, but we have done numerous taste tests on blindfolded volunteers who have also had 250 micrograms of LSD-25 administered beforehand. 35% of the volunteers said that FreeBSD tasted sort of orange, whereas Linux(R) tasted like purple haze. Neither group mentioned any significant variances in temperature. We eventually had to throw the results of this survey out entirely anyway when we found that too many volunteers were wandering out of the room during the tests, thus skewing the results. We think most of the volunteers are at Apple now, working on their new "scratch and sniff" GUI. It is a funny old business we are in! Seriously, FreeBSD uses the HLT (halt) instruction when the system is idle thus lowering its energy consumption and therefore the heat it generates. Also if you have ACPI (Advanced Configuration and Power Interface) configured, then FreeBSD can also put the CPU into a low power mode. [[letmeoutofhere]] === Who is scratching in my memory banks?? _Q._ Is there anything "odd" that FreeBSD does when compiling the kernel which would cause the memory to make a scratchy sound? When compiling (and for a brief moment after recognizing the floppy drive upon startup, as well), a strange scratchy sound emanates from what appears to be the memory banks. _A._ Yes! You will see frequent references to "daemons" in the BSD documentation, and what most people do not know is that this refers to genuine, non-corporeal entities that now possess your computer. The scratchy sound coming from your memory is actually high-pitched whispering exchanged among the daemons as they best decide how to deal with various system administration tasks. If the noise gets to you, a good `fdisk /mbr` from DOS will get rid of them, but do not be surprised if they react adversely and try to stop you. In fact, if at any point during the exercise you hear the satanic voice of Bill Gates coming from the built-in speaker, take off running and do not ever look back! Freed from the counterbalancing influence of the BSD daemons, the twin demons of DOS and Windows(R) are often able to re-assert total control over your machine to the eternal damnation of your soul. Now that you know, given a choice you would probably prefer to get used to the scratchy noises, no? [[changing-lightbulbs]] === How many FreeBSD hackers does it take to change a lightbulb? One thousand, one hundred and sixty-nine: Twenty-three to complain to -CURRENT about the lights being out; Four to claim that it is a configuration problem, and that such matters really belong on -questions; Three to submit PRs about it, one of which is misfiled under doc and consists only of "it's dark"; One to commit an untested lightbulb which breaks buildworld, then back it out five minutes later; Eight to flame the PR originators for not including patches in their PRs; Five to complain about buildworld being broken; Thirty-one to answer that it works for them, and they must have updated at a bad time; One to post a patch for a new lightbulb to -hackers; One to complain that he had patches for this three years ago, but when he sent them to -CURRENT they were just ignored, and he has had bad experiences with the PR system; besides, the proposed new lightbulb is non-reflexive; Thirty-seven to scream that lightbulbs do not belong in the base system, that committers have no right to do things like this without consulting the Community, and WHAT IS -CORE DOING ABOUT IT!? Two hundred to complain about the color of the bicycle shed; Three to point out that the patch breaks man:style[9]; Seventeen to complain that the proposed new lightbulb is under GPL; Five hundred and eighty-six to engage in a flame war about the comparative advantages of the GPL, the BSD license, the MIT license, the NPL, and the personal hygiene of unnamed FSF founders; Seven to move various portions of the thread to -chat and -advocacy; One to commit the suggested lightbulb, even though it shines dimmer than the old one; Two to back it out with a furious flame of a commit message, arguing that FreeBSD is better off in the dark than with a dim lightbulb; Forty-six to argue vociferously about the backing out of the dim lightbulb and demanding a statement from -core; Eleven to request a smaller lightbulb so it will fit their Tamagotchi if we ever decide to port FreeBSD to that platform; Seventy-three to complain about the SNR on -hackers and -chat and unsubscribe in protest; Thirteen to post "unsubscribe", "How do I unsubscribe?", or "Please remove me from the list", followed by the usual footer; One to commit a working lightbulb while everybody is too busy flaming everybody else to notice; Thirty-one to point out that the new lightbulb would shine 0.364% brighter if compiled with TenDRA (although it will have to be reshaped into a cube), and that FreeBSD should therefore switch to TenDRA instead of GCC; One to complain that the new lightbulb lacks fairings; Nine (including the PR originators) to ask "what is MFC?"; Fifty-seven to complain about the lights being out two weeks after the bulb has been changed. _{nik} adds:_ _I was laughing quite hard at this._ _And then I thought, "Hang on, shouldn't there be '1 to document it.' in that list somewhere?"_ _And then I was enlightened :-)_ _{tabthorpe}_ says: "None, _real_ FreeBSD hackers are not afraid of the dark!" [[dev-null]] === Where does data written to [.filename]#/dev/null# go? It goes into a special data sink in the CPU where it is converted to heat which is vented through the heatsink / fan assembly. This is why CPU cooling is increasingly important; as people get used to faster processors, they become careless with their data and more and more of it ends up in [.filename]#/dev/null#, overheating their CPUs. If you delete [.filename]#/dev/null# (which effectively disables the CPU data sink) your CPU may run cooler but your system will quickly become constipated with all that excess data and start to behave erratically. If you have a fast network connection you can cool down your CPU by reading data out of [.filename]#/dev/random# and sending it off somewhere; however you run the risk of overheating your network connection and [.filename]#/# or angering your ISP, as most of the data will end up getting converted to heat by their equipment, but they generally have good cooling, so if you do not overdo it you should be OK. _Paul Robinson adds:_ There are other methods. As every good sysadmin knows, it is part of standard practice to send data to the screen of interesting variety to keep all the pixies that make up your picture happy. Screen pixies (commonly mis-typed or re-named as "pixels") are categorized by the type of hat they wear (red, green or blue) and will hide or appear (thereby showing the color of their hat) whenever they receive a little piece of food. Video cards turn data into pixie-food, and then send them to the pixies - the more expensive the card, the better the food, so the better behaved the pixies are. They also need constant stimulation - this is why screen savers exist. To take your suggestions further, you could just throw the random data to console, thereby letting the pixies consume it. This causes no heat to be produced at all, keeps the pixies happy and gets rid of your data quite quickly, even if it does make things look a bit messy on your screen. Incidentally, as an ex-admin of a large ISP who experienced many problems attempting to maintain a stable temperature in a server room, I would strongly discourage people sending the data they do not want out to the network. The fairies who do the packet switching and routing get annoyed by it as well. [[punk-my-friend]] === My colleague sits at the computer too much, how can I prank her? Install package:games/sl[] and wait for her to mistype `sl` for `ls`. [[advanced]] == Advanced Topics [[learn-advanced]] === How can I learn more about FreeBSD's internals? See the extref:{arch-handbook}[FreeBSD Architecture Handbook]. Additionally, much general UNIX(R) knowledge is directly applicable to FreeBSD. [[how-to-contribute]] === How can I contribute to FreeBSD? What can I do to help? We accept all types of contributions: documentation, code, and even art. See the article on extref:{contributing}[Contributing to FreeBSD] for specific advice on how to do this. And thanks for the thought! [[define-snap-release]] === What are snapshots and releases? There are currently {rel-numbranch} active/semi-active branches in the FreeBSD http://svnweb.FreeBSD.org/base/[Subversion Repository]. (Earlier branches are only changed very rarely, which is why there are only {rel-numbranch} active branches of development): * {rel2-releng} AKA {rel2-stable} * {rel-releng} AKA {rel-stable} * {rel-head-releng} AKA _-CURRENT_ AKA {rel-head} `HEAD` is not an actual branch tag. It is a symbolic constant for the current, non-branched development stream known as _-CURRENT_. Right now, _-CURRENT_ is the {rel-head-relx} development stream; the {rel-stable} branch, {rel-releng}, forked off from _-CURRENT_ in {rel-relengdate} and the {rel2-stable} branch, {rel2-releng}, forked off from _-CURRENT_ in {rel2-relengdate}. [[kernel-panic-troubleshooting]] === How can I make the most of the data I see when my kernel panics? Here is typical kernel panic: [.programlisting] .... Fatal trap 12: page fault while in kernel mode fault virtual address = 0x40 fault code = supervisor read, page not present instruction pointer = 0x8:0xf014a7e5 stack pointer = 0x10:0xf4ed6f24 frame pointer = 0x10:0xf4ed6f28 code segment = base 0x0, limit 0xfffff, type 0x1b = DPL 0, pres 1, def32 1, gran 1 processor eflags = interrupt enabled, resume, IOPL = 0 current process = 80 (mount) interrupt mask = trap number = 12 panic: page fault .... This message is not enough. While the instruction pointer value is important, it is also configuration dependent as it varies depending on the kernel image. If it is a [.filename]#GENERIC# kernel image from one of the snapshots, it is possible for somebody else to track down the offending function, but for a custom kernel, only you can tell us where the fault occurred. To proceed: [.procedure] ==== . Write down the instruction pointer value. Note that the `0x8:` part at the beginning is not significant in this case: it is the `0xf0xxxxxx` part that we want. . When the system reboots, do the following: + [source,shell] .... % nm -n kernel.that.caused.the.panic | grep f0xxxxxx .... + where `f0xxxxxx` is the instruction pointer value. The odds are you will not get an exact match since the symbols in the kernel symbol table are for the entry points of functions and the instruction pointer address will be somewhere inside a function, not at the start. If you do not get an exact match, omit the last digit from the instruction pointer value and try again: + [source,shell] .... % nm -n kernel.that.caused.the.panic | grep f0xxxxx .... + If that does not yield any results, chop off another digit. Repeat until there is some sort of output. The result will be a possible list of functions which caused the panic. This is a less than exact mechanism for tracking down the point of failure, but it is better than nothing. ==== However, the best way to track down the cause of a panic is by capturing a crash dump, then using man:kgdb[1] to generate a stack trace on the crash dump. In any case, the method is this: [.procedure] ==== . Make sure that the following line is included in the kernel configuration file: + [.programlisting] .... makeoptions DEBUG=-g # Build kernel with gdb(1) debug symbols .... . Change to the [.filename]#/usr/src# directory: + [source,shell] .... # cd /usr/src .... . Compile the kernel: + [source,shell] .... # make buildkernel KERNCONF=MYKERNEL .... . Wait for man:make[1] to finish compiling. + [source,shell] .... # make installkernel KERNCONF=MYKERNEL .... . Reboot. ==== [NOTE] ==== If `KERNCONF` is not included, the [.filename]#GENERIC# kernel will instead be built and installed. ==== The man:make[1] process will have built two kernels. [.filename]#/usr/obj/usr/src/sys/MYKERNEL/kernel# and [.filename]#/usr/obj/usr/src/sys/MYKERNEL/kernel.debug#. [.filename]#kernel# was installed as [.filename]#/boot/kernel/kernel#, while [.filename]#kernel.debug# can be used as the source of debugging symbols for man:kgdb[1]. To capture a crash dump, edit [.filename]#/etc/rc.conf# and set `dumpdev` to point to either the swap partition or `AUTO`. This will cause the man:rc[8] scripts to use the man:dumpon[8] command to enable crash dumps. This command can also be run manually. After a panic, the crash dump can be recovered using man:savecore[8]; if `dumpdev` is set in [.filename]#/etc/rc.conf#, the man:rc[8] scripts will run man:savecore[8] automatically and put the crash dump in [.filename]#/var/crash#. [NOTE] ==== FreeBSD crash dumps are usually the same size as physical RAM. Therefore, make sure there is enough space in [.filename]#/var/crash# to hold the dump. Alternatively, run man:savecore[8] manually and have it recover the crash dump to another directory with more room. It is possible to limit the size of the crash dump by using `options MAXMEM=N` where _N_ is the size of kernel's memory usage in KBs. For example, for 1 GB of RAM, limit the kernel's memory usage to 128 MB, so that the crash dump size will be 128 MB instead of 1 GB. ==== Once the crash dump has been recovered , get a stack trace as follows: [source,shell] .... % kgdb /usr/obj/usr/src/sys/MYKERNEL/kernel.debug /var/crash/vmcore.0 (kgdb) backtrace .... Note that there may be several screens worth of information. Ideally, use man:script[1] to capture all of them. Using the unstripped kernel image with all the debug symbols should show the exact line of kernel source code where the panic occurred. The stack trace is usually read from the bottom up to trace the exact sequence of events that lead to the crash. man:kgdb[1] can also be used to print out the contents of various variables or structures to examine the system state at the time of the crash. [TIP] ==== If a second computer is available, man:kgdb[1] can be configured to do remote debugging, including setting breakpoints and single-stepping through the kernel code. ==== [NOTE] ==== If `DDB` is enabled and the kernel drops into the debugger, a panic and a crash dump can be forced by typing `panic` at the `ddb` prompt. It may stop in the debugger again during the panic phase. If it does, type `continue` and it will finish the crash dump. ==== [[dlsym-failure]] === Why has dlsym() stopped working for ELF executables? The ELF toolchain does not, by default, make the symbols defined in an executable visible to the dynamic linker. Consequently `dlsym()` searches on handles obtained from calls to `dlopen(NULL, flags)` will fail to find such symbols. To search, using `dlsym()`, for symbols present in the main executable of a process, link the executable using the `--export-dynamic` option to the ELF linker (man:ld[1]). [[change-kernel-address-space]] === How can I increase or reduce the kernel address space on i386? By default, the kernel address space is 1 GB (2 GB for PAE) for i386. When running a network-intensive server or using ZFS, this will probably not be enough. Add the following line to the kernel configuration file to increase available space and rebuild the kernel: [.programlisting] .... options KVA_PAGES=N .... To find the correct value of _N_, divide the desired address space size (in megabytes) by four. (For example, it is `512` for 2 GB.) [[acknowledgments]] == Acknowledgments This innocent little Frequently Asked Questions document has been written, rewritten, edited, folded, spindled, mutilated, eviscerated, contemplated, discombobulated, cogitated, regurgitated, rebuilt, castigated, and reinvigorated over the last decade, by a cast of hundreds if not thousands. Repeatedly. We wish to thank every one of the people responsible, and we encourage you to extref:{contributing}[join them] in making this FAQ even better. diff --git a/documentation/content/en/books/handbook/x11/_index.adoc b/documentation/content/en/books/handbook/x11/_index.adoc index 0776bda76b..ddce9e8ad8 100644 --- a/documentation/content/en/books/handbook/x11/_index.adoc +++ b/documentation/content/en/books/handbook/x11/_index.adoc @@ -1,1642 +1,1642 @@ --- title: Chapter 5. The X Window System part: Part I. Getting Started prev: books/handbook/ports next: books/handbook/partii description: This chapter describes how to install and configure Xorg on FreeBSD, which provides the open source X Window System used to provide a graphical environment tags: ["X11", "Xorg", "TrueType", "DE", "KDE", "Plasma", "Xfce", "Gnome", "XDM", "SDDM", "GDM", "KMS", "Intel", "AMD", "NVIDIA", "Anti-Aliased"] showBookMenu: true weight: 7 path: "/books/handbook/" --- [[x11]] = The X Window System :doctype: book :toc: macro :toclevels: 1 :icons: font :sectnums: :sectnumlevels: 6 :sectnumoffset: 5 :partnums: :source-highlighter: rouge :experimental: :images-path: books/handbook/x11/ ifdef::env-beastie[] ifdef::backend-html5[] :imagesdir: ../../../../images/{images-path} endif::[] ifndef::book[] include::shared/authors.adoc[] include::shared/mirrors.adoc[] include::shared/releases.adoc[] include::shared/attributes/attributes-{{% lang %}}.adoc[] include::shared/{{% lang %}}/teams.adoc[] include::shared/{{% lang %}}/mailing-lists.adoc[] include::shared/{{% lang %}}/urls.adoc[] toc::[] endif::[] ifdef::backend-pdf,backend-epub3[] include::../../../../../shared/asciidoctor.adoc[] endif::[] endif::[] ifndef::env-beastie[] toc::[] include::../../../../../shared/asciidoctor.adoc[] endif::[] [[x11-synopsis]] == Synopsis An installation of FreeBSD using bsdinstall does not automatically install a graphical user interface. This chapter describes how to install and configure Xorg, which provides the open source X Window System used to provide a graphical environment. It then describes how to find and install a desktop environment or window manager. [NOTE] ==== Users who prefer an installation method that automatically configures the Xorg should refer to https://ghostbsd.org[GhostBSD], https://www.midnightbsd.org[MidnightBSD] or https://nomadbsd.org[NomadBSD]. ==== For more information on the video hardware that Xorg supports, refer to the http://www.x.org/[x.org] website. After reading this chapter, you will know: * The various components of the X Window System, and how they interoperate. * How to install and configure Xorg. * How to install and configure several window managers and desktop environments. * How to use TrueType(R) fonts in Xorg. * How to set up your system for graphical logins (XDM). Before reading this chapter, you should: * Know how to install additional third-party software as described in crossref:ports[ports,Installing Applications: Packages and Ports]. [[x-understanding]] == Terminology While it is not necessary to understand all of the details of the various components in the X Window System and how they interact, some basic knowledge of these components can be useful. X server:: X was designed from the beginning to be network-centric, and adopts a "client-server" model. In this model, the "X server" runs on the computer that has the keyboard, monitor, and mouse attached. The server's responsibility includes tasks such as managing the display, handling input from the keyboard and mouse, and handling input or output from other devices such as a tablet or a video projector. This confuses some people, because the X terminology is exactly backward to what they expect. They expect the "X server" to be the big powerful machine down the hall, and the "X client" to be the machine on their desk. X client:: Each X application, such as XTerm or Firefox, is a "client". A client sends messages to the server such as "Please draw a window at these coordinates", and the server sends back messages such as "The user just clicked on the OK button". + In a home or small office environment, the X server and the X clients commonly run on the same computer. It is also possible to run the X server on a less powerful computer and to run the X applications on a more powerful system. In this scenario, the communication between the X client and server takes place over the network. window manager:: X does not dictate what windows should look like on-screen, how to move them around with the mouse, which keystrokes should be used to move between windows, what the title bars on each window should look like, whether or not they have close buttons on them, and so on. Instead, X delegates this responsibility to a separate window manager application. There are http://www.xwinman.org/[dozens of window managers] available. Each window manager provides a different look and feel: some support virtual desktops, some allow customized keystrokes to manage the desktop, some have a "Start" button, and some are themeable, allowing a complete change of the desktop's look-and-feel. Window managers are available in the [.filename]#x11-wm# category of the Ports Collection. + Each window manager uses a different configuration mechanism. Some expect configuration file written by hand while others provide graphical tools for most configuration tasks. desktop environment:: KDE and GNOME are considered to be desktop environments as they include an entire suite of applications for performing common desktop tasks. These may include office suites, web browsers, and games. focus policy:: The window manager is responsible for the mouse focus policy. This policy provides some means for choosing which window is actively receiving keystrokes and it should also visibly indicate which window is currently active. + One focus policy is called "click-to-focus". In this model, a window becomes active upon receiving a mouse click. In the "focus-follows-mouse" policy, the window that is under the mouse pointer has focus and the focus is changed by pointing at another window. If the mouse is over the root window, then this window is focused. In the "sloppy-focus" model, if the mouse is moved over the root window, the most recently used window still has the focus. With sloppy-focus, focus is only changed when the cursor enters a new window, and not when exiting the current window. In the "click-to-focus" policy, the active window is selected by mouse click. The window may then be raised and appear in front of all other windows. All keystrokes will now be directed to this window, even if the cursor is moved to another window. + Different window managers support different focus models. All of them support click-to-focus, and the majority of them also support other policies. Consult the documentation for the window manager to determine which focus models are available. widgets:: Widget is a term for all of the items in the user interface that can be clicked or manipulated in some way. This includes buttons, check boxes, radio buttons, icons, and lists. A widget toolkit is a set of widgets used to create graphical applications. There are several popular widget toolkits, including Qt, used by KDE, and GTK+, used by GNOME. As a result, applications will have a different look and feel, depending upon which widget toolkit was used to create the application. [[x-install]] == Installing Xorg On FreeBSD, Xorg can be installed as a package or port. The binary package can be installed quickly but with fewer options for customization: [source,shell] .... # pkg install xorg .... To build and install from the Ports Collection: [source,shell] .... # cd /usr/ports/x11/xorg # make install clean .... Either of these installations results in the complete Xorg system being installed. Binary packages are the best option for most users. A smaller version of the X system suitable for experienced users is available in package:x11/xorg-minimal[]. Most of the documents, libraries, and applications will not be installed. Some applications require these additional components to function. [[x-config]] == Xorg Configuration [[x-config-quick-start]] === Quick Start Xorg supports most common video cards, keyboards, and pointing devices. [TIP] ==== Video cards, monitors, and input devices are automatically detected and do not require any manual configuration. Do not create [.filename]#xorg.conf# or run a `-configure` step unless automatic configuration fails. ==== [.procedure] . If Xorg has been used on this computer before, move or remove any existing configuration files: + [source,shell] .... # mv /etc/X11/xorg.conf ~/xorg.conf.etc # mv /usr/local/etc/X11/xorg.conf ~/xorg.conf.localetc .... . Add the user who will run Xorg to the `video` or `wheel` group to enable 3D acceleration when available. To add user _jru_ to whichever group is available: + [source,shell] .... # pw groupmod video -m jru || pw groupmod wheel -m jru .... . The `TWM` window manager is included by default. It is started when Xorg starts: + [source,shell] .... % startx .... . On some older versions of FreeBSD, the system console must be set to man:vt[4] before switching back to the text console will work properly. See <>. [[x-config-user-group]] === User Group for Accelerated Video Access to [.filename]#/dev/dri# is needed to allow 3D acceleration on video cards. It is usually simplest to add the user who will be running X to either the `video` or `wheel` group. Here, man:pw[8] is used to add user _slurms_ to the `video` group, or to the `wheel` group if there is no `video` group: [source,shell] .... # pw groupmod video -m slurms || pw groupmod wheel -m slurms .... [[x-config-kms]] === Kernel Mode Setting (`KMS`) When the computer switches from displaying the console to a higher screen resolution for X, it must set the video output _mode_. Recent versions of `Xorg` use a system inside the kernel to do these mode changes more efficiently. Older versions of FreeBSD use man:sc[4], which is not aware of the `KMS` system. The end result is that after closing X, the system console is blank, even though it is still working. The newer man:vt[4] console avoids this problem. Add this line to [.filename]#/boot/loader.conf# to enable man:vt[4]: [.programlisting] .... kern.vty=vt .... [[x-config-files]] === Configuration Files Manual configuration is usually not necessary. Please do not manually create configuration files unless autoconfiguration does not work. [[x-config-files-directory]] ==== Directory Xorg looks in several directories for configuration files. [.filename]#/usr/local/etc/X11/# is the recommended directory for these files on FreeBSD. Using this directory helps keep application files separate from operating system files. Storing configuration files in the legacy [.filename]#/etc/X11/# still works. However, this mixes application files with the base FreeBSD files and is not recommended. [[x-config-files-single-or-multi]] ==== Single or Multiple Files It is easier to use multiple files that each configure a specific setting than the traditional single [.filename]#xorg.conf#. These files are stored in the [.filename]#xorg.conf.d/# subdirectory of the main configuration file directory. The full path is typically [.filename]#/usr/local/etc/X11/xorg.conf.d/#. Examples of these files are shown later in this section. The traditional single [.filename]#xorg.conf# still works, but is neither as clear nor as flexible as multiple files in the [.filename]#xorg.conf.d/# subdirectory. [[x-config-video-cards]] === Video Cards The Ports framework provides the drm graphics drivers necessary for X11 operation on recent hardware. Users can use one of the following drivers available from package:graphics/drm-kmod[]. These drivers use interfaces in the kernel that are normally private. As such, it is strongly recommended that the drivers be built via the ports system via the `PORTS_MODULES` variable. With `PORTS_MODULES`, every time you build the kernel, the corresponding port(s) containing kernel modules are re-built against the updated sources. This ensures the kernel module stays in-sync with the kernel itself. The kernel and ports trees should be updated together for maximum compatibility. You can add `PORTS_MODULES` to your [.filename]#/etc/make.conf# file to ensure all kernels you build rebuild this module. Advanced users can add it to their kernel config files with the `makeoptions` directive. If you run GENERIC and use freebsd-update, you can just build the [.filename]#graphics/drm-kmod# or [.filename]#x11/nvidia-driver# port after each `freebsd-update install` invocation. [example] ==== [.filename]#/etc/make.conf# [.programlisting] .... SYSDIR=path/to/src/sys PORTS_MODULES=graphics/drm-kmod x11/nvidia-driver .... This will rebuild everything, but can select one or the other depending on which GPU / graphics card you have. ==== [[x-config-video-cards-ports]] Intel KMS driver, Radeon KMS driver, AMD KMS driver:: 2D and 3D acceleration is supported on most Intel KMS driver graphics cards provided by Intel. + Driver name: `i915kms` + 2D and 3D acceleration is supported on most older Radeon KMS driver graphics cards provided by AMD. + Driver name: `radeonkms` + 2D and 3D acceleration is supported on most newer AMD KMS driver graphics cards provided by AMD. + Driver name: `amdgpu` + For reference, please see https://en.wikipedia.org/wiki/List_of_Intel_graphics_processing_units[] or https://en.wikipedia.org/wiki/List_of_AMD_graphics_processing_units[] for a list of supported GPUs. [[x-config-video-cards-intel]] Intel(R):: 3D acceleration is supported on most Intel(R) graphics up to Ivy Bridge (HD Graphics 2500, 4000, and P4000), including Iron Lake (HD Graphics) and Sandy Bridge (HD Graphics 2000). + Driver name: `intel` + For reference, see https://en.wikipedia.org/wiki/List_of_Intel_graphics_processing_units[]. [[x-config-video-cards-radeon]] AMD(R) Radeon:: 2D and 3D acceleration is supported on Radeon cards up to and including the HD6000 series. + Driver name: `radeon` + For reference, see https://en.wikipedia.org/wiki/List_of_AMD_graphics_processing_units[]. [[x-config-video-cards-nvidia]] NVIDIA:: Several NVIDIA drivers are available in the [.filename]#x11# category of the Ports Collection. Install the driver that matches the video card. + For reference, see https://en.wikipedia.org/wiki/List_of_Nvidia_graphics_processing_units[]. + Kernel support for NVIDIA cards is found in either the [.filename]#x11/nvidia-driver# port or the [.filename]#x11/nvidia-driver-xxx# port. Modern cards use the former. Legacy cards use the -xxx ports, where xxx is one of 304, 340 or 390 indicating the version of the driver. For those, fill in the `-xxx` using the http://download.nvidia.com/XFree86/FreeBSD-x86_64/465.19.01/README/[ Supported NVIDIA GPU Products ] page. This page lists the devices supported by different versions of the driver. Legacy drivers run on both i386 and amd64. The current driver only supports amd64. Read http://download.nvidia.com/XFree86/FreeBSD-x86_64/465.19.01/README/[installation and configuration of NVIDIA driver] for details. While we recommend this driver be rebuilt with each kernel rebuild for maximum safety, it uses almost no private kernel interfaces and is usually safe across kernel updates. [[x-config-video-cards-hybrid]] Hybrid Combination Graphics:: Some notebook computers add additional graphics processing units to those built into the chipset or processor. _Optimus_ combines Intel(R) and NVIDIA hardware. _Switchable Graphics_ or _Hybrid Graphics_ are a combination of an Intel(R) or AMD(R) processor and an AMD(R) Radeon `GPU`. + Implementations of these hybrid graphics systems vary, and Xorg on FreeBSD is not able to drive all versions of them. + Some computers provide a `BIOS` option to disable one of the graphics adapters or select a _discrete_ mode which can be used with one of the standard video card drivers. For example, it is sometimes possible to disable the NVIDIA `GPU` in an Optimus system. The Intel(R) video can then be used with an Intel(R) driver. + `BIOS` settings depend on the model of computer. In some situations, both ``GPU``s can be left enabled, but creating a configuration file that only uses the main `GPU` in the `Device` section is enough to make such a system functional. [[x-config-video-cards-other]] Other Video Cards:: Drivers for some less-common video cards can be found in the [.filename]#x11-drivers# directory of the Ports Collection. + Cards that are not supported by a specific driver might still be usable with the package:x11-drivers/xf86-video-vesa[] driver. This driver is installed by package:x11/xorg[]. It can also be installed manually as package:x11-drivers/xf86-video-vesa[]. Xorg attempts to use this driver when a specific driver is not found for the video card. + package:x11-drivers/xf86-video-scfb[] is a similar nonspecialized video driver that works on many `UEFI` and ARM(R) computers. [[x-config-video-cards-file]] Setting the Video Driver in a File:: To set the Intel(R) driver in a configuration file: + [[x-config-video-cards-file-intel]] .Select Intel(R) Video Driver in a File [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/driver-intel.conf# [.programlisting] .... Section "Device" Identifier "Card0" Driver "intel" # BusID "PCI:1:0:0" EndSection .... If more than one video card is present, the `BusID` identifier can be uncommented and set to select the desired card. A list of video card bus ``ID``s can be displayed with `pciconf -lv | grep -B3 display`. ==== + To set the Radeon driver in a configuration file: + [[x-config-video-cards-file-radeon]] .Select Radeon Video Driver in a File [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/driver-radeon.conf# [.programlisting] .... Section "Device" Identifier "Card0" Driver "radeon" EndSection .... ==== + To set the `VESA` driver in a configuration file: + [[x-config-video-cards-file-vesa]] .Select `VESA` Video Driver in a File [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/driver-vesa.conf# [.programlisting] .... Section "Device" Identifier "Card0" Driver "vesa" EndSection .... ==== + To set the `scfb` driver for use with a `UEFI` or ARM(R) computer: + [[x-config-video-cards-file-scfb]] .Select `scfb` Video Driver in a File [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/driver-scfb.conf# [.programlisting] .... Section "Device" Identifier "Card0" Driver "scfb" EndSection .... ==== [[x-config-monitors]] === Monitors Almost all monitors support the Extended Display Identification Data standard (`EDID`). Xorg uses `EDID` to communicate with the monitor and detect the supported resolutions and refresh rates. Then it selects the most appropriate combination of settings to use with that monitor. Other resolutions supported by the monitor can be chosen by setting the desired resolution in configuration files, or after the X server has been started with man:xrandr[1]. [[x-config-monitors-xrandr]] Using man:xrandr[1]:: Run man:xrandr[1] without any parameters to see a list of video outputs and detected monitor modes: + [source,shell] .... % xrandr Screen 0: minimum 320 x 200, current 3000 x 1920, maximum 8192 x 8192 DVI-0 connected primary 1920x1200+1080+0 (normal left inverted right x axis y axis) 495mm x 310mm 1920x1200 59.95*+ 1600x1200 60.00 1280x1024 85.02 75.02 60.02 1280x960 60.00 1152x864 75.00 1024x768 85.00 75.08 70.07 60.00 832x624 74.55 800x600 75.00 60.32 640x480 75.00 60.00 720x400 70.08 DisplayPort-0 disconnected (normal left inverted right x axis y axis) HDMI-0 disconnected (normal left inverted right x axis y axis) .... + This shows that the `DVI-0` output is being used to display a screen resolution of 1920x1200 pixels at a refresh rate of about 60 Hz. Monitors are not attached to the `DisplayPort-0` and `HDMI-0` connectors. + Any of the other display modes can be selected with man:xrandr[1]. For example, to switch to 1280x1024 at 60 Hz: + [source,shell] .... % xrandr --output DVI-0 --mode 1280x1024 --rate 60 .... + A common task is using the external video output on a notebook computer for a video projector. + The type and quantity of output connectors varies between devices, and the name given to each output varies from driver to driver. What one driver calls `HDMI-1`, another might call `HDMI1`. So the first step is to run man:xrandr[1] to list all the available outputs: + [source,shell] .... % xrandr Screen 0: minimum 320 x 200, current 1366 x 768, maximum 8192 x 8192 LVDS1 connected 1366x768+0+0 (normal left inverted right x axis y axis) 344mm x 193mm 1366x768 60.04*+ 1024x768 60.00 800x600 60.32 56.25 640x480 59.94 VGA1 connected (normal left inverted right x axis y axis) 1280x1024 60.02 + 75.02 1280x960 60.00 1152x864 75.00 1024x768 75.08 70.07 60.00 832x624 74.55 800x600 72.19 75.00 60.32 56.25 640x480 75.00 72.81 66.67 60.00 720x400 70.08 HDMI1 disconnected (normal left inverted right x axis y axis) DP1 disconnected (normal left inverted right x axis y axis) .... + Four outputs were found: the built-in panel `LVDS1`, and external `VGA1`, `HDMI1`, and `DP1` connectors. + The projector has been connected to the `VGA1` output. man:xrandr[1] is now used to set that output to the native resolution of the projector and add the additional space to the right side of the desktop: + [source,shell] .... % xrandr --output VGA1 --auto --right-of LVDS1 .... + `--auto` chooses the resolution and refresh rate detected by `EDID`. If the resolution is not correctly detected, a fixed value can be given with `--mode` instead of the `--auto` statement. For example, most projectors can be used with a 1024x768 resolution, which is set with `--mode 1024x768`. + man:xrandr[1] is often run from [.filename]#.xinitrc# to set the appropriate mode when X starts. [[x-config-monitors-files]] Setting Monitor Resolution in a File:: To set a screen resolution of 1024x768 in a configuration file: + .Set Screen Resolution in a File [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/screen-resolution.conf# [.programlisting] .... Section "Screen" Identifier "Screen0" Device "Card0" SubSection "Display" Modes "1024x768" EndSubSection EndSection .... ==== + The few monitors that do not have `EDID` can be configured by setting `HorizSync` and `VertRefresh` to the range of frequencies supported by the monitor. + .Manually Setting Monitor Frequencies [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/monitor0-freq.conf# [.programlisting] .... Section "Monitor" Identifier "Monitor0" HorizSync 30-83 # kHz VertRefresh 50-76 # Hz EndSection .... ==== [[x-config-input]] === Input Devices [[x-config-input-keyboard]] ==== Keyboards [[x-config-input-keyboard-layout]] Keyboard Layout:: The standardized location of keys on a keyboard is called a _layout_. Layouts and other adjustable parameters are listed in man:xkeyboard-config[7]. + A United States layout is the default. To select an alternate layout, set the `XkbLayout` and `XkbVariant` options in an `InputClass`. This will be applied to all input devices that match the class. + This example selects a French keyboard layout. + .Setting a Keyboard Layout [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/keyboard-fr.conf# [.programlisting] .... Section "InputClass" Identifier "KeyboardDefaults" MatchIsKeyboard "on" Option "XkbLayout" "fr" EndSection .... ==== + .Setting Multiple Keyboard Layouts [example] ==== Set United States, Spanish, and Ukrainian keyboard layouts. Cycle through these layouts by pressing kbd:[Alt+Shift]. package:x11/xxkb[] or package:x11/sbxkb[] can be used for improved layout switching control and current layout indicators. [.filename]#/usr/local/etc/X11/xorg.conf.d/kbd-layout-multi.conf# [.programlisting] .... Section "InputClass" Identifier "All Keyboards" MatchIsKeyboard "yes" Option "XkbLayout" "us, es, ua" EndSection .... ==== [[x-config-input-keyboard-zap]] Closing Xorg From the Keyboard:: X can be closed with a combination of keys. By default, that key combination is not set because it conflicts with keyboard commands for some applications. Enabling this option requires changes to the keyboard `InputDevice` section: + .Enabling Keyboard Exit from X [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/keyboard-zap.conf# [.programlisting] .... Section "InputClass" Identifier "KeyboardDefaults" MatchIsKeyboard "on" Option "XkbOptions" "terminate:ctrl_alt_bksp" EndSection .... ==== [[x11-input-mice]] ==== Mice and Pointing Devices [IMPORTANT] ==== If using package:xorg-server[] 1.20.8 or later under FreeBSD {rel121-current} and not using man:moused[8], add `kern.evdev.rcpt_mask=12` to [.filename]#/etc/sysctl.conf#. ==== Many mouse parameters can be adjusted with configuration options. See man:mousedrv[4] for a full list. [[x11-input-mice-buttons]] Mouse Buttons:: The number of buttons on a mouse can be set in the mouse `InputDevice` section of [.filename]#xorg.conf#. To set the number of buttons to 7: + .Setting the Number of Mouse Buttons [example] ==== [.filename]#/usr/local/etc/X11/xorg.conf.d/mouse0-buttons.conf# [.programlisting] .... Section "InputDevice" Identifier "Mouse0" Option "Buttons" "7" EndSection .... ==== [[x-config-manual-configuration]] === Manual Configuration In some cases, Xorg autoconfiguration does not work with particular hardware, or a different configuration is desired. For these cases, a custom configuration file can be created. [WARNING] ==== Do not create manual configuration files unless required. Unnecessary manual configuration can prevent proper operation. ==== A configuration file can be generated by Xorg based on the detected hardware. This file is often a useful starting point for custom configurations. Generating an [.filename]#xorg.conf#: [source,shell] .... # Xorg -configure .... The configuration file is saved to [.filename]#/root/xorg.conf.new#. Make any changes desired, then test that file (using `-retro` so there is a visible background) with: [source,shell] .... # Xorg -retro -config /root/xorg.conf.new .... After the new configuration has been adjusted and tested, it can be split into smaller files in the normal location, [.filename]#/usr/local/etc/X11/xorg.conf.d/#. [[x-fonts]] == Using Fonts in Xorg [[type1]] === Type1 Fonts The default fonts that ship with Xorg are less than ideal for typical desktop publishing applications. Large presentation fonts show up jagged and unprofessional looking, and small fonts are almost completely unintelligible. However, there are several free, high quality Type1 (PostScript(R)) fonts available which can be readily used with Xorg. For instance, the URW font collection (package:x11-fonts/urwfonts[]) includes high quality versions of standard type1 fonts (Times Roman(TM), Helvetica(TM), Palatino(TM) and others). The Freefonts collection (package:x11-fonts/freefonts[]) includes many more fonts, but most of them are intended for use in graphics software such as the Gimp, and are not complete enough to serve as screen fonts. In addition, Xorg can be configured to use TrueType(R) fonts with a minimum of effort. For more details on this, see the man:X[7] manual page or <>. To install the above Type1 font collections from binary packages, run the following commands: [source,shell] .... # pkg install urwfonts .... Alternatively, to build from the Ports Collection, run the following commands: [source,shell] .... # cd /usr/ports/x11-fonts/urwfonts # make install clean .... And likewise with the freefont or other collections. To have the X server detect these fonts, add an appropriate line to the X server configuration file ([.filename]#/etc/X11/xorg.conf#), which reads: [.programlisting] .... FontPath "/usr/local/share/fonts/urwfonts/" .... Alternatively, at the command line in the X session run: [source,shell] .... % xset fp+ /usr/local/share/fonts/urwfonts % xset fp rehash .... This will work but will be lost when the X session is closed, unless it is added to the startup file ([.filename]#~/.xinitrc# for a normal `startx` session, or [.filename]#~/.xsession# when logging in through a graphical login manager like XDM). A third way is to use the new [.filename]#/usr/local/etc/fonts/local.conf# as demonstrated in <>. [[truetype]] === TrueType(R) Fonts Xorg has built in support for rendering TrueType(R) fonts. There are two different modules that can enable this functionality. The freetype module is used in this example because it is more consistent with the other font rendering back-ends. To enable the freetype module just add the following line to the `"Module"` section of [.filename]#/etc/X11/xorg.conf#. [.programlisting] .... Load "freetype" .... Now make a directory for the TrueType(R) fonts (for example, [.filename]#/usr/local/share/fonts/TrueType#) and copy all of the TrueType(R) fonts into this directory. Keep in mind that TrueType(R) fonts cannot be directly taken from an Apple(R) Mac(R); they must be in UNIX(R)/MS-DOS(R)/Windows(R) format for use by Xorg. Once the files have been copied into this directory, use mkfontscale to create a [.filename]#fonts.dir#, so that the X font renderer knows that these new files have been installed. `mkfontscale` can be installed as a package: [source,shell] .... # pkg install mkfontscale .... Then create an index of X font files in a directory: [source,shell] .... # cd /usr/local/share/fonts/TrueType # mkfontscale .... Now add the TrueType(R) directory to the font path. This is just the same as described in <>: [source,shell] .... % xset fp+ /usr/local/share/fonts/TrueType % xset fp rehash .... or add a `FontPath` line to [.filename]#xorg.conf#. Now Gimp, LibreOffice, and all of the other X applications should now recognize the installed TrueType(R) fonts. Extremely small fonts (as with text in a high resolution display on a web page) and extremely large fonts (within LibreOffice) will look much better now. [[antialias]] === Anti-Aliased Fonts All fonts in Xorg that are found in [.filename]#/usr/local/share/fonts/# and [.filename]#~/.fonts/# are automatically made available for anti-aliasing to Xft-aware applications. Most recent applications are Xft-aware, including KDE, GNOME, and Firefox. To control which fonts are anti-aliased, or to configure anti-aliasing properties, create (or edit, if it already exists) the file [.filename]#/usr/local/etc/fonts/local.conf#. Several advanced features of the Xft font system can be tuned using this file; this section describes only some simple possibilities. For more details, please see man:fonts-conf[5]. This file must be in XML format. Pay careful attention to case, and make sure all tags are properly closed. The file begins with the usual XML header followed by a DOCTYPE definition, and then the `` tag: [.programlisting] .... .... As previously stated, all fonts in [.filename]#/usr/local/share/fonts/# as well as [.filename]#~/.fonts/# are already made available to Xft-aware applications. To add another directory outside of these two directory trees, add a line like this to [.filename]#/usr/local/etc/fonts/local.conf#: [.programlisting] .... /path/to/my/fonts .... After adding new fonts, and especially new font directories, rebuild the font caches: [source,shell] .... # fc-cache -f .... Anti-aliasing makes borders slightly fuzzy, which makes very small text more readable and removes "staircases" from large text, but can cause eyestrain if applied to normal text. To exclude font sizes smaller than 14 point from anti-aliasing, include these lines: [.programlisting] .... 14 false 14 false .... Spacing for some monospaced fonts might also be inappropriate with anti-aliasing. This seems to be an issue with KDE, in particular. One possible fix is to force the spacing for such fonts to be 100. Add these lines: [.programlisting] .... fixed mono console mono .... (this aliases the other common names for fixed fonts as `"mono"`), and then add: [.programlisting] .... mono 100 .... Certain fonts, such as Helvetica, may have a problem when anti-aliased. Usually this manifests itself as a font that seems cut in half vertically. At worst, it may cause applications to crash. To avoid this, consider adding the following to [.filename]#local.conf#: [.programlisting] .... Helvetica sans-serif .... After editing [.filename]#local.conf#, make certain to end the file with the `` tag. Not doing this will cause changes to be ignored. Users can add personalized settings by creating their own [.filename]#~/.config/fontconfig/fonts.conf#. This file uses the same `XML` format described above. One last point: with an LCD screen, sub-pixel sampling may be desired. This basically treats the (horizontally separated) red, green and blue components separately to improve the horizontal resolution; the results can be dramatic. To enable this, add the line somewhere in [.filename]#local.conf#: [.programlisting] .... unknown rgb .... [NOTE] ==== Depending on the sort of display, `rgb` may need to be changed to `bgr`, `vrgb` or `vbgr`: experiment and see which works best. ==== [[x-xdm]] == The X Display Manager Xorg provides an X Display Manager, XDM, which can be used for login session management. XDM provides a graphical interface for choosing which display server to connect to and for entering authorization information such as a login and password combination. This section demonstrates how to configure the X Display Manager on FreeBSD. Some desktop environments provide their own graphical login manager. Refer to <> for instructions on how to configure the GNOME Display Manager and <> for instructions on how to configure the KDE Display Manager. === Configuring XDM To install XDM, use the package:x11/xdm[] package or port. Once installed, XDM can be configured to run when the machine boots up by adding the following line to [.filename]#/etc/rc.conf#: [.programlisting] .... xdm_enable="YES" .... XDM will run on the ninth virtual terminal by default. The XDM configuration directory is located in [.filename]#/usr/local/etc/X11/xdm#. This directory contains several files used to change the behavior and appearance of XDM, as well as a few scripts and programs used to set up the desktop when XDM is running. <> summarizes the function of each of these files. -The exact syntax and usage of these files is described in man:xdm[1]. +The exact syntax and usage of these files is described in man:xdm[8]. [[xdm-config-files]] .XDM Configuration Files [cols="1,1", frame="none", options="header"] |=== | File | Description |[.filename]#Xaccess# |The protocol for connecting to XDM is called the X Display Manager Connection Protocol (`XDMCP`). This file is a client authorization ruleset for controlling `XDMCP` connections from remote machines. By default, this file does not allow any remote clients to connect. |[.filename]#Xresources# |This file controls the look and feel of the XDM display chooser and login screens. The default configuration is a simple rectangular login window with the hostname of the machine displayed at the top in a large font and "Login:" and "Password:" prompts below. The format of this file is identical to the app-defaults file described in the Xorg documentation. |[.filename]#Xservers# |The list of local and remote displays the chooser should provide as login choices. |[.filename]#Xsession# |Default session script for logins which is run by XDM after a user has logged in. This points to a customized session script in [.filename]#~/.xsession#. |[.filename]#Xsetup_#* |Script to automatically launch applications before displaying the chooser or login interfaces. There is a script for each display being used, named [.filename]#Xsetup_*#, where `*` is the local display number. Typically these scripts run one or two programs in the background such as `xconsole`. |[.filename]#xdm-config# |Global configuration for all displays running on this machine. |[.filename]#xdm-errors# |Contains errors generated by the server program. If a display that XDM is trying to start hangs, look at this file for error messages. These messages are also written to the user's [.filename]#~/.xsession-errors# on a per-session basis. |[.filename]#xdm-pid# |The running process `ID` of XDM. |=== === Configuring Remote Access By default, only users on the same system can login using XDM. To enable users on other systems to connect to the display server, edit the access control rules and enable the connection listener. To configure XDM to listen for any remote connection, comment out the `DisplayManager.requestPort` line in [.filename]#/usr/local/etc/X11/xdm/xdm-config# by putting a `!` in front of it: [source,shell] .... ! SECURITY: do not listen for XDMCP or Chooser requests ! Comment out this line if you want to manage X terminals with xdm DisplayManager.requestPort: 0 .... Save the edits and restart XDM. -To restrict remote access, look at the example entries in [.filename]#/usr/local/etc/X11/xdm/Xaccess# and refer to man:xdm[1] for further information. +To restrict remote access, look at the example entries in [.filename]#/usr/local/etc/X11/xdm/Xaccess# and refer to man:xdm[8] for further information. [[x11-wm]] == Desktop Environments This section describes how to install three popular desktop environments on a FreeBSD system. A desktop environment can range from a simple window manager to a complete suite of desktop applications. Over a hundred desktop environments are available in the [.filename]#x11-wm# category of the Ports Collection. [[x11-wm-gnome]] === GNOME GNOME is a user-friendly desktop environment. It includes a panel for starting applications and displaying status, a desktop, a set of tools and applications, and a set of conventions that make it easy for applications to cooperate and be consistent with each other. More information regarding GNOME on FreeBSD can be found at https://www.FreeBSD.org/gnome[https://www.FreeBSD.org/gnome]. That web site contains additional documentation about installing, configuring, and managing GNOME on FreeBSD. This desktop environment can be installed from a package: [source,shell] .... # pkg install gnome3 .... To instead build GNOME from ports, use the following command. GNOME is a large application and will take some time to compile, even on a fast computer. [source,shell] .... # cd /usr/ports/x11/gnome3 # make install clean .... GNOME requires [.filename]#/proc# to be mounted. Add this line to [.filename]#/etc/fstab# to mount this file system automatically during system startup: [.programlisting] .... proc /proc procfs rw 0 0 .... GNOME uses D-Bus for a message bus and hardware abstraction. These applications are automatically installed as dependencies of GNOME. Enable them in [.filename]#/etc/rc.conf# so they will be started when the system boots: [.programlisting] .... dbus_enable="YES" .... After installation, configure Xorg to start GNOME. The easiest way to do this is to enable the GNOME Display Manager, GDM, which is installed as part of the GNOME package or port. It can be enabled by adding this line to [.filename]#/etc/rc.conf#: [.programlisting] .... gdm_enable="YES" .... It is often desirable to also start all GNOME services. To achieve this, add a second line to [.filename]#/etc/rc.conf#: [.programlisting] .... gnome_enable="YES" .... GDM will start automatically when the system boots. A second method for starting GNOME is to type `startx` from the command-line after configuring [.filename]#~/.xinitrc#. If this file already exists, replace the line that starts the current window manager with one that starts [.filename]#/usr/local/bin/gnome-session#. If this file does not exist, create it with this command: [source,shell] .... % echo "exec /usr/local/bin/gnome-session" > ~/.xinitrc .... A third method is to use XDM as the display manager. In this case, create an executable [.filename]#~/.xsession#: [source,shell] .... % echo "exec /usr/local/bin/gnome-session" > ~/.xsession .... [[x11-wm-kde]] === KDE KDE is another easy-to-use desktop environment. This desktop provides a suite of applications with a consistent look and feel, a standardized menu and toolbars, keybindings, color-schemes, internationalization, and a centralized, dialog-driven desktop configuration. More information on KDE can be found at http://www.kde.org/[http://www.kde.org/]. For FreeBSD-specific information, consult http://freebsd.kde.org/[http://freebsd.kde.org]. To install the KDE package, type: [source,shell] .... # pkg install x11/kde5 .... To instead build the KDE port, use the following command. Installing the port will provide a menu for selecting which components to install. KDE is a large application and will take some time to compile, even on a fast computer. [source,shell] .... # cd /usr/ports/x11/kde5 # make install clean .... KDE requires [.filename]#/proc# to be mounted. Add this line to [.filename]#/etc/fstab# to mount this file system automatically during system startup: [.programlisting] .... proc /proc procfs rw 0 0 .... KDE uses D-Bus for a message bus and hardware abstraction. These applications are automatically installed as dependencies of KDE. Enable them in [.filename]#/etc/rc.conf# so they will be started when the system boots: [.programlisting] .... dbus_enable="YES" .... Since KDE Plasma 5, the KDE Display Manager, KDM is no longer developed. A possible replacement is SDDM. To install it, type: [source,shell] .... # pkg install x11/sddm .... Add this line to [.filename]#/etc/rc.conf#: [.programlisting] .... sddm_enable="YES" .... A second method for launching KDE Plasma is to type `startx` from the command line. For this to work, the following line is needed in [.filename]#~/.xinitrc#: [.programlisting] .... exec ck-launch-session startplasma-x11 .... A third method for starting KDE Plasma is through XDM. To do so, create an executable [.filename]#~/.xsession# as follows: [source,shell] .... % echo "exec ck-launch-session startplasma-x11" > ~/.xsession .... Once KDE Plasma is started, refer to its built-in help system for more information on how to use its various menus and applications. [[x11-wm-xfce]] === Xfce Xfce is a desktop environment based on the GTK+ toolkit used by GNOME. However, it is more lightweight and provides a simple, efficient, easy-to-use desktop. It is fully configurable, has a main panel with menus, applets, and application launchers, provides a file manager and sound manager, and is themeable. Since it is fast, light, and efficient, it is ideal for older or slower machines with memory limitations. More information on Xfce can be found at http://www.xfce.org/[http://www.xfce.org]. To install the Xfce package: [source,shell] .... # pkg install xfce .... Alternatively, to build the port: [source,shell] .... # cd /usr/ports/x11-wm/xfce4 # make install clean .... Xfce uses D-Bus for a message bus. This application is automatically installed as dependency of Xfce. Enable it in [.filename]#/etc/rc.conf# so it will be started when the system boots: [.programlisting] .... dbus_enable="YES" .... Unlike GNOME or KDE, Xfce does not provide its own login manager. In order to start Xfce from the command line by typing `startx`, first create [.filename]#~/.xinitrc# with this command: [source,shell] .... % echo ". /usr/local/etc/xdg/xfce4/xinitrc" > ~/.xinitrc .... An alternate method is to use XDM. To configure this method, create an executable [.filename]#~/.xsession#: [source,shell] .... % echo ". /usr/local/etc/xdg/xfce4/xinitrc" > ~/.xsession .... [[x-compiz-fusion]] == Installing Compiz Fusion One way to make using a desktop computer more pleasant is with nice 3D effects. Installing the Compiz Fusion package is easy, but configuring it requires a few steps that are not described in the port's documentation. [[x-compiz-video-card]] === Setting up the FreeBSD nVidia Driver Desktop effects can cause quite a load on the graphics card. For an nVidia-based graphics card, the proprietary driver is required for good performance. Users of other graphics cards can skip this section and continue with the [.filename]#xorg.conf# configuration. To determine which nVidia driver is needed see the extref:{faq}[FAQ question on the subject, idp59950544]. Having determined the correct driver to use for your card, installation is as simple as installing any other package. For example, to install the latest driver: [source,shell] .... # pkg install x11/nvidia-driver .... The driver will create a kernel module, which needs to be loaded at system startup. Use man:sysrc[8] to load the module at startup: [source,shell] .... # sysrc kld_list+="nvidia" .... Alternatively, add the following line to [.filename]#/boot/loader.conf#: [.programlisting] .... nvidia_load="YES" .... [NOTE] ==== To immediately load the kernel module into the running kernel issue a command like `kldload nvidia`. However, it has been noted that some versions of Xorg will not function properly if the driver is not loaded at boot time. After editing [.filename]#/boot/loader.conf#, a reboot is recommended. Improper settings in [.filename]#/boot/loader.conf# can cause the system not to boot properly. ==== With the kernel module loaded, you normally only need to change a single line in [.filename]#xorg.conf# to enable the proprietary driver: Find the following line in [.filename]#/etc/X11/xorg.conf#: [.programlisting] .... Driver "nv" .... and change it to: [.programlisting] .... Driver "nvidia" .... Start the GUI as usual, and you should be greeted by the nVidia splash. Everything should work as usual. [[xorg-configuration]] === Configuring `xorg.conf` for Desktop Effects To enable Compiz Fusion, [.filename]#/etc/X11/xorg.conf# needs to be modified: Add the following section to enable composite effects: [.programlisting] .... Section "Extensions" Option "Composite" "Enable" EndSection .... Locate the "Screen" section which should look similar to the one below: [.programlisting] .... Section "Screen" Identifier "Screen0" Device "Card0" Monitor "Monitor0" ... .... and add the following two lines (after "Monitor" will do): [.programlisting] .... DefaultDepth 24 Option "AddARGBGLXVisuals" "True" .... Locate the "Subsection" that refers to the screen resolution that you wish to use. For example, if you wish to use 1280x1024, locate the section that follows. If the desired resolution does not appear in any subsection, you may add the relevant entry by hand: [.programlisting] .... SubSection "Display" Viewport 0 0 Modes "1280x1024" EndSubSection .... A color depth of 24 bits is needed for desktop composition, change the above subsection to: [.programlisting] .... SubSection "Display" Viewport 0 0 Depth 24 Modes "1280x1024" EndSubSection .... Finally, confirm that the "glx" and "extmod" modules are loaded in the "Module" section: [.programlisting] .... Section "Module" Load "extmod" Load "glx" ... .... The preceding can be done automatically with package:x11/nvidia-xconfig[] by running (as root): [source,shell] .... # nvidia-xconfig --add-argb-glx-visuals # nvidia-xconfig --composite # nvidia-xconfig --depth=24 .... [[compiz-fusion]] === Installing and Configuring Compiz Fusion Installing Compiz Fusion is as simple as any other package: [source,shell] .... # pkg install x11-wm/compiz-fusion .... When the installation is finished, start your graphic desktop and at a terminal, enter the following commands (as a normal user): [source,shell] .... % compiz --replace --sm-disable --ignore-desktop-hints ccp & % emerald --replace & .... Your screen will flicker for a few seconds, as your window manager (e.g., Metacity if you are using GNOME) is replaced by Compiz Fusion. Emerald takes care of the window decorations (i.e., close, minimize, maximize buttons, title bars and so on). You may convert this to a trivial script and have it run at startup automatically (e.g., by adding to "Sessions" in a GNOME desktop): [.programlisting] .... #! /bin/sh compiz --replace --sm-disable --ignore-desktop-hints ccp & emerald --replace & .... Save this in your home directory as, for example, [.filename]#start-compiz# and make it executable: [source,shell] .... % chmod +x ~/start-compiz .... Then use the GUI to add it to [.guimenuitem]#Startup Programs# (located in [.guimenuitem]#System#, [.guimenuitem]#Preferences#, [.guimenuitem]#Sessions# on a GNOME desktop). To actually select all the desired effects and their settings, execute (again as a normal user) the Compiz Config Settings Manager: [source,shell] .... % ccsm .... [NOTE] ==== In GNOME, this can also be found in the [.guimenuitem]#System#, [.guimenuitem]#Preferences# menu. ==== If you have selected "gconf support" during the build, you will also be able to view these settings using `gconf-editor` under `apps/compiz`. [[x11-troubleshooting]] == Troubleshooting If the mouse does not work, you will need to first configure it before proceeding. In recent Xorg versions, the `InputDevice` sections in [.filename]#xorg.conf# are ignored in favor of the autodetected devices. To restore the old behavior, add the following line to the `ServerLayout` or `ServerFlags` section of this file: [.programlisting] .... Option "AutoAddDevices" "false" .... Input devices may then be configured as in previous versions, along with any other options needed (e.g., keyboard layout switching). [NOTE] ==== [WARNING] ===== This section contains partially outdated information. The HAL daemon (hald) is no longer a part of the FreeBSD desktop setup. ===== As previously explained the hald daemon will, by default, automatically detect your keyboard. There are chances that your keyboard layout or model will not be correct, desktop environments like GNOME, KDE or Xfce provide tools to configure the keyboard. However, it is possible to set the keyboard properties directly either with the help of the man:setxkbmap[1] utility or with a hald's configuration rule. For example if, one wants to use a PC 102 keys keyboard coming with a french layout, we have to create a keyboard configuration file for hald called [.filename]#x11-input.fdi# and saved in the [.filename]#/usr/local/etc/hal/fdi/policy# directory. This file should contain the following lines: [.programlisting] .... pc102 fr .... If this file already exists, just copy and add to your file the lines regarding the keyboard configuration. You will have to reboot your machine to force hald to read this file. It is possible to do the same configuration from an X terminal or a script with this command line: [source,shell] .... % setxkbmap -model pc102 -layout fr .... [.filename]#/usr/local/share/X11/xkb/rules/base.lst# lists the various keyboard, layouts and options available. ==== The [.filename]#xorg.conf.new# configuration file may now be tuned to taste. Open the file in a text editor such as man:emacs[1] or man:ee[1]. If the monitor is an older or unusual model that does not support autodetection of sync frequencies, those settings can be added to [.filename]#xorg.conf.new# under the `"Monitor"` section: [.programlisting] .... Section "Monitor" Identifier "Monitor0" VendorName "Monitor Vendor" ModelName "Monitor Model" HorizSync 30-107 VertRefresh 48-120 EndSection .... Most monitors support sync frequency autodetection, making manual entry of these values unnecessary. For the few monitors that do not support autodetection, avoid potential damage by only entering values provided by the manufacturer. X allows DPMS (Energy Star) features to be used with capable monitors. The man:xset[1] program controls the time-outs and can force standby, suspend, or off modes. If you wish to enable DPMS features for your monitor, you must add the following line to the monitor section: [.programlisting] .... Option "DPMS" .... While the [.filename]#xorg.conf.new# configuration file is still open in an editor, select the default resolution and color depth desired. This is defined in the `"Screen"` section: [.programlisting] .... Section "Screen" Identifier "Screen0" Device "Card0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Viewport 0 0 Depth 24 Modes "1024x768" EndSubSection EndSection .... The `DefaultDepth` keyword describes the color depth to run at by default. This can be overridden with the `-depth` command line switch to man:Xorg[1]. The `Modes` keyword describes the resolution to run at for the given color depth. Note that only VESA standard modes are supported as defined by the target system's graphics hardware. In the example above, the default color depth is twenty-four bits per pixel. At this color depth, the accepted resolution is 1024 by 768 pixels. Finally, write the configuration file and test it using the test mode given above. [NOTE] ==== One of the tools available to assist you during troubleshooting process are the Xorg log files, which contain information on each device that the Xorg server attaches to. Xorg log file names are in the format of [.filename]#/var/log/Xorg.0.log#. The exact name of the log can vary from [.filename]#Xorg.0.log# to [.filename]#Xorg.8.log# and so forth. ==== If all is well, the configuration file needs to be installed in a common location where man:Xorg[1] can find it. This is typically [.filename]#/etc/X11/xorg.conf# or [.filename]#/usr/local/etc/X11/xorg.conf#. [source,shell] .... # cp xorg.conf.new /etc/X11/xorg.conf .... The Xorg configuration process is now complete. Xorg may be now started with the man:startx[1] utility. -The Xorg server may also be started with the use of man:xdm[1]. +The Xorg server may also be started with the use of man:xdm[8]. === Configuration with Intel(R) `i810` Graphics Chipsets Configuration with Intel(R) i810 integrated chipsets requires the [.filename]#agpgart# AGP programming interface for Xorg to drive the card. See the man:agp[4] driver manual page for more information. This will allow configuration of the hardware as any other graphics board. Note on systems without the man:agp[4] driver compiled in the kernel, trying to load the module with man:kldload[8] will not work. This driver has to be in the kernel at boot time through being compiled in or using [.filename]#/boot/loader.conf#. === Adding a Widescreen Flatpanel to the Mix This section assumes a bit of advanced configuration knowledge. If attempts to use the standard configuration tools above have not resulted in a working configuration, there is information enough in the log files to be of use in getting the setup working. Use of a text editor will be necessary. Current widescreen (WSXGA, WSXGA+, WUXGA, WXGA, WXGA+, et.al.) formats support 16:10 and 10:9 formats or aspect ratios that can be problematic. Examples of some common screen resolutions for 16:10 aspect ratios are: * 2560x1600 * 1920x1200 * 1680x1050 * 1440x900 * 1280x800 At some point, it will be as easy as adding one of these resolutions as a possible `Mode` in the `Section "Screen"` as such: [.programlisting] .... Section "Screen" Identifier "Screen0" Device "Card0" Monitor "Monitor0" DefaultDepth 24 SubSection "Display" Viewport 0 0 Depth 24 Modes "1680x1050" EndSubSection EndSection .... Xorg is smart enough to pull the resolution information from the widescreen via I2C/DDC information so it knows what the monitor can handle as far as frequencies and resolutions. If those `ModeLines` do not exist in the drivers, one might need to give Xorg a little hint. Using [.filename]#/var/log/Xorg.0.log# one can extract enough information to manually create a `ModeLine` that will work. Simply look for information resembling this: [.programlisting] .... (II) MGA(0): Supported additional Video Mode: (II) MGA(0): clock: 146.2 MHz Image Size: 433 x 271 mm (II) MGA(0): h_active: 1680 h_sync: 1784 h_sync_end 1960 h_blank_end 2240 h_border: 0 (II) MGA(0): v_active: 1050 v_sync: 1053 v_sync_end 1059 v_blanking: 1089 v_border: 0 (II) MGA(0): Ranges: V min: 48 V max: 85 Hz, H min: 30 H max: 94 kHz, PixClock max 170 MHz .... This information is called EDID information. Creating a `ModeLine` from this is just a matter of putting the numbers in the correct order: [.programlisting] .... ModeLine <4 horiz. timings> <4 vert. timings> .... So that the `ModeLine` in `Section "Monitor"` for this example would look like this: [.programlisting] .... Section "Monitor" Identifier "Monitor1" VendorName "Bigname" ModelName "BestModel" ModeLine "1680x1050" 146.2 1680 1784 1960 2240 1050 1053 1059 1089 Option "DPMS" EndSection .... Now having completed these simple editing steps, X should start on your new widescreen monitor. [[compiz-troubleshooting]] === Troubleshooting Compiz Fusion ==== I have installed Compiz Fusion, and after running the commands you mention, my windows are left without title bars and buttons. What is wrong? You are probably missing a setting in [.filename]#/etc/X11/xorg.conf#. Review this file carefully and check especially the `DefaultDepth` and `AddARGBGLXVisuals` directives. ==== When I run the command to start Compiz Fusion, the X server crashes and I am back at the console. What is wrong? If you check [.filename]#/var/log/Xorg.0.log#, you will probably find error messages during the X startup. The most common would be: [source,shell] .... (EE) NVIDIA(0): Failed to initialize the GLX module; please check in your X (EE) NVIDIA(0): log file that the GLX module has been loaded in your X (EE) NVIDIA(0): server, and that the module is the NVIDIA GLX module. If (EE) NVIDIA(0): you continue to encounter problems, Please try (EE) NVIDIA(0): reinstalling the NVIDIA driver. .... This is usually the case when you upgrade Xorg. You will need to reinstall the package:x11/nvidia-driver[] package so glx is built again.