diff --git a/en_US.ISO8859-1/books/handbook/eresources/chapter.sgml b/en_US.ISO8859-1/books/handbook/eresources/chapter.sgml index cd4c660689..6f1963a6b3 100644 --- a/en_US.ISO8859-1/books/handbook/eresources/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/eresources/chapter.sgml @@ -1,1928 +1,1928 @@ Resources on the Internet The rapid pace of FreeBSD progress makes print media impractical as a means of following the latest developments. Electronic resources are the best, if not often the only, way stay informed of the latest advances. Since FreeBSD is a volunteer effort, the user community itself also generally serves as a technical support department of sorts, with electronic mail and USENET news being the most effective way of reaching that community. The most important points of contact with the FreeBSD user community are outlined below. If you are aware of other resources not mentioned here, please send them to the &a.doc; so that they may also be included. Mailing Lists Though many of the FreeBSD development members read USENET, we cannot always guarantee that we will get to your questions in a timely fashion (or at all) if you post them only to one of the comp.unix.bsd.freebsd.* groups. By addressing your questions to the appropriate mailing list you will reach both us and a concentrated FreeBSD audience, invariably assuring a better (or at least faster) response. The charters for the various lists are given at the bottom of this document. Please read the charter before joining or sending mail to any list. Most of our list subscribers now receive many hundreds of FreeBSD related messages every day, and by setting down charters and rules for proper use we are striving to keep the signal-to-noise ratio of the lists high. To do less would see the mailing lists ultimately fail as an effective communications medium for the project. Archives are kept for all of the mailing lists and can be searched using the FreeBSD World Wide Web server. The keyword searchable archive offers an excellent way of finding answers to frequently asked questions and should be consulted before posting a question. List Summary General lists: The following are general lists which anyone is free (and encouraged) to join: List Purpose &a.cvsall.name; Changes made to the FreeBSD source tree &a.advocacy.name; FreeBSD Evangelism &a.announce.name; Important events and project milestones &a.arch.name; Architecture and design discussions &a.bugbusters.name; Discussions pertaining to the maintenance of the FreeBSD problem report database and related tools &a.bugs.name; Bug reports &a.chat.name; Non-technical items related to the FreeBSD community &a.config.name; Development of FreeBSD installation and configuration tools &a.current.name; Discussion concerning the use of &os.current; &a.isp.name; Issues for Internet Service Providers using FreeBSD &a.jobs.name; FreeBSD employment and consulting opportunities &a.newbies.name; New FreeBSD users activities and discussions &a.policy.name; FreeBSD Core team policy decisions. Low volume, and read-only &a.questions.name; User questions and technical support &a.security-notifications.name; Security notifications &a.stable.name; Discussion concerning the use of &os.stable; &a.test.name; Where to send your test messages instead of one of the actual lists Technical lists: The following lists are for technical discussion. You should read the charter for each list carefully before joining or sending mail to one as there are firm guidelines for their use and content. List Purpose &a.afs.name; Porting AFS to FreeBSD &a.aic7xxx.name; Developing drivers for the &adaptec; AIC 7xxx &a.alpha.name; Porting FreeBSD to the Alpha &a.amd64.name; Porting FreeBSD to AMD64 systems &a.arm.name; Porting FreeBSD to &arm; processors &a.atm.name; Using ATM networking with FreeBSD &a.audit.name; Source code audit project &a.binup.name; Design and development of the binary update system &a.cluster.name; Using FreeBSD in a clustered environment &a.cvsweb.name; CVSweb maintenance &a.database.name; Discussing database use and development under FreeBSD &a.doc.name; Creating FreeBSD related documents &a.emulation.name; Emulation of other systems such as Linux/DOS/&windows; &a.firewire.name; FreeBSD &firewire; (iLink, IEEE 1394) technical discussion &a.fs.name; File systems &a.gnome.name; Porting GNOME and GNOME applications &a.hackers.name; General technical discussion &a.hardware.name; General discussion of hardware for running FreeBSD &a.i18n.name; FreeBSD Internationalization &a.ia32.name; FreeBSD on the IA-32 (&intel; x86) platform &a.ia64.name; Porting FreeBSD to Intel's upcoming IA64 systems &a.ipfw.name; Technical discussion concerning the redesign of the IP firewall code &a.isdn.name; ISDN developers &a.java.name; &java; developers and people porting &jdk;s to FreeBSD &a.kde.name; Porting KDE and KDE applications &a.lfs.name; Porting LFS to FreeBSD &a.libh.name; The second generation installation and package system &a.mips.name; Porting FreeBSD to &mips; &a.mobile.name; Discussions about mobile computing &a.mozilla.name; Porting Mozilla to FreeBSD &a.multimedia.name; Multimedia applications &a.newbus.name; Technical discussions about bus architecture &a.net.name; Networking discussion and TCP/IP source code &a.openoffice.name; Porting OpenOffice.org and &staroffice; to FreeBSD &a.performance.name; Performance tuning questions for high performance/load installations &a.platforms.name; Concerning ports to non-Intel architecture platforms &a.ports.name; Discussion of the ports collection &a.ports-bugs.name; Discussion of the ports bugs/PRs &a.ppc.name; Porting FreeBSD to the &powerpc; &a.qa.name; Discussion of Quality Assurance, usually pending a release &a.realtime.name; Development of realtime extensions to FreeBSD &a.scsi.name; The SCSI subsystem &a.security.name; Security issues affecting FreeBSD &a.small.name; Using FreeBSD in embedded applications &a.smp.name; Design discussions for [A]Symmetric MultiProcessing &a.sparc.name; Porting FreeBSD to &sparc; based systems &a.standards.name; FreeBSD's conformance to the C99 and the &posix; standards &a.threads.name; Threading in FreeBSD &a.testing.name; FreeBSD Performance and Stability Tests &a.tokenring.name; Support Token Ring in FreeBSD Limited lists: The following lists are for more specialized (and demanding) audiences and are probably not of interest to the general public. It is also a good idea to establish a presence in the technical lists before joining one of these limited lists so that you will understand the communications etiquette involved. List Purpose &a.hubs.name; People running mirror sites (infrastructural support) &a.usergroups.name; User group coordination &a.vendors.name; Vendors pre-release coordination &a.www.name; Maintainers of www.FreeBSD.org Digest lists: All of the above lists are available in a digest format. Once subscribed to a list, you can change your digest options in your account options section. CVS lists: The following lists are for people interested in seeing the log messages for changes to various areas of the source tree. They are Read-Only lists and should not have mail sent to them. List Source area Area Description (source for) &a.cvsall.name; /usr/(CVSROOT|doc|ports|projects|src) All changes to any place in the tree (superset of other cvs commit lists) &a.cvs-doc.name; /usr/doc All changes to the doc tree &a.cvs-ports.name; /usr/ports All changes to the ports tree &a.cvs-projects.name; /usr/projects All changes to the projects tree &a.cvs-src.name; /usr/src All changes to the src tree How to Subscribe To subscribe to a list, click on the list name above or go to &a.mailman.lists.link; and click on the list that you are interested in. The list page should contain all of the necessary subscription instructions. To actually post to a given list you simply send mail to <listname@FreeBSD.org>. It will then be redistributed to mailing list members world-wide. To unsubscribe yourself from a list, click on the URL found at the bottom of every email received from the list. It is also possible to send an email to freebsd-[listname]-unsubscribe@FreeBSD.org to unsubscribe yourself. Again, we would like to request that you keep discussion in the technical mailing lists on a technical track. If you are only interested in important announcements then it is suggested that you join the &a.announce;, which is intended only for infrequent traffic. List Charters All FreeBSD mailing lists have certain basic rules which must be adhered to by anyone using them. Failure to comply with these guidelines will result in two (2) written warnings from the FreeBSD Postmaster postmaster@FreeBSD.org, after which, on a third offense, the poster will removed from all FreeBSD mailing lists and filtered from further posting to them. We regret that such rules and measures are necessary at all, but today's Internet is a pretty harsh environment, it would seem, and many fail to appreciate just how fragile some of its mechanisms are. Rules of the road: The topic of any posting should adhere to the basic charter of the list it is posted to, e.g. if the list is about technical issues then your posting should contain technical discussion. Ongoing irrelevant chatter or flaming only detracts from the value of the mailing list for everyone on it and will not be tolerated. For free-form discussion on no particular topic, the &a.chat; is freely available and should be used instead. No posting should be made to more than 2 mailing lists, and only to 2 when a clear and obvious need to post to both lists exists. For most lists, there is already a great deal of subscriber overlap and except for the most esoteric mixes (say -stable & -scsi), there really is no reason to post to more than one list at a time. If a message is sent to you in such a way that multiple mailing lists appear on the Cc line then the Cc line should also be trimmed before sending it out again. You are still responsible for your own cross-postings, no matter who the originator might have been. Personal attacks and profanity (in the context of an argument) are not allowed, and that includes users and developers alike. Gross breaches of netiquette, like excerpting or reposting private mail when permission to do so was not and would not be forthcoming, are frowned upon but not specifically enforced. However, there are also very few cases where such content would fit within the charter of a list and it would therefore probably rate a warning (or ban) on that basis alone. Advertising of non-FreeBSD related products or services is strictly prohibited and will result in an immediate ban if it is clear that the offender is advertising by spam. Individual list charters: &a.afs.name; Andrew File System This list is for discussion on porting and using AFS from CMU/Transarc &a.announce.name; Important events / milestones This is the mailing list for people interested only in occasional announcements of significant FreeBSD events. This includes announcements about snapshots and other releases. It contains announcements of new FreeBSD capabilities. It may contain calls for volunteers etc. This is a low volume, strictly moderated mailing list. &a.arch.name; Architecture and design discussions This list is for discussion of the FreeBSD architecture. Messages will mostly be kept strictly technical in nature. Examples of suitable topics are: How to re-vamp the build system to have several customized builds running at the same time. What needs to be fixed with VFS to make Heidemann layers work. How do we change the device driver interface to be able to use the same drivers cleanly on many buses and architectures. How to write a network driver. &a.audit.name; Source code audit project This is the mailing list for the FreeBSD source code audit project. Although this was originally intended for security-related changes, its charter has been expanded to review any code changes. This list is very heavy on patches, and is probably of no interest to the average FreeBSD user. Security discussions not related to a particular code change are held on freebsd-security. Conversely, all developers are encouraged to send their patches here for review, especially if they touch a part of the system where a bug may adversely affect the integrity of the system. &a.binup.name; FreeBSD Binary Update Project This list exists to provide discussion for the binary update system, or binup. Design issues, implementation details, patches, bug reports, status reports, feature requests, commit logs, and all other things related to binup are fair game. &a.bugbusters.name; Coordination of the Problem Report handling effort The purpose of this list is to serve as a coordination and discussion forum for the Bugmeister, his Bugbusters, and any other parties who have a genuine interest in the PR database. This list is not for discussions about specific bugs, patches or PRs. &a.bugs.name; Bug reports This is the mailing list for reporting bugs in FreeBSD. Whenever possible, bugs should be submitted using the &man.send-pr.1; command or the WEB interface to it. &a.chat.name; Non technical items related to the FreeBSD community This list contains the overflow from the other lists about non-technical, social information. It includes discussion about whether Jordan looks like a toon ferret or not, whether or not to type in capitals, who is drinking too much coffee, where the best beer is brewed, who is brewing beer in their basement, and so on. Occasional announcements of important events (such as upcoming parties, weddings, births, new jobs, etc) can be made to the technical lists, but the follow ups should be directed to this -chat list. &a.core.name; FreeBSD core team This is an internal mailing list for use by the core members. Messages can be sent to it when a serious FreeBSD-related matter requires arbitration or high-level scrutiny. &a.current.name; Discussions about the use of &os.current; This is the mailing list for users of &os.current;. It includes warnings about new features coming out in -CURRENT that will affect the users, and instructions on steps that must be taken to remain -CURRENT. Anyone running CURRENT must subscribe to this list. This is a technical mailing list for which strictly technical content is expected. &a.cvsweb.name; FreeBSD CVSweb Project Technical discussions about use, development and maintenance of FreeBSD-CVSweb. &a.doc.name; Documentation project This mailing list is for the discussion of issues and projects related to the creation of documentation for FreeBSD. The members of this mailing list are collectively referred to as The FreeBSD Documentation Project. It is an open list; feel free to join and contribute! &a.firewire.name; &firewire; (iLink, IEEE 1394) This is a mailing list for discussion of the design and implementation of a &firewire; (aka IEEE 1394 aka iLink) subsystem for FreeBSD. Relevant topics specifically include the standards, bus devices and their protocols, adapter boards/cards/chips sets, and the architecture and implementation of code for their proper support. &a.fs.name; File systems Discussions concerning FreeBSD file systems. This is a technical mailing list for which strictly technical content is expected. &a.gnome.name; GNOME Discussions concerning The GNOME Desktop Environment for FreeBSD systems. This is a technical mailing list for which strictly technical content is expected. &a.ipfw.name; IP Firewall This is the forum for technical discussions concerning the redesign of the IP firewall code in FreeBSD. This is a technical mailing list for which strictly technical content is expected. &a.ia64.name; Porting FreeBSD to IA64 This is a technical mailing list for individuals actively working on porting FreeBSD to the IA-64 platform from Intel, to bring up problems or discuss alternative solutions. Individuals interested in following the technical discussion are also welcome. &a.isdn.name; ISDN Communications This is the mailing list for people discussing the development of ISDN support for FreeBSD. &a.java.name; &java; Development This is the mailing list for people discussing the development of significant &java; applications for FreeBSD and the porting and maintenance of &jdk;s. &a.kde.name; KDE Discussions concerning KDE on FreeBSD systems. This is a technical mailing list for which strictly technical content is expected. &a.hackers.name; Technical discussions This is a forum for technical discussions related to FreeBSD. This is the primary technical mailing list. It is for individuals actively working on FreeBSD, to bring up problems or discuss alternative solutions. Individuals interested in following the technical discussion are also welcome. This is a technical mailing list for which strictly technical content is expected. &a.hardware.name; General discussion of FreeBSD hardware General discussion about the types of hardware that FreeBSD runs on, various problems and suggestions concerning what to buy or avoid. &a.hubs.name; Mirror sites Announcements and discussion for people who run FreeBSD mirror sites. &a.isp.name; Issues for Internet Service Providers This mailing list is for discussing topics relevant to Internet Service Providers (ISPs) using FreeBSD. This is a technical mailing list for which strictly technical content is expected. &a.newbies.name; Newbies activities discussion We cover any of the activities of newbies that are not already dealt with elsewhere, including: independent learning and problem solving techniques, finding and using resources and asking for help elsewhere, how to use mailing lists and which lists to use, general chat, making mistakes, boasting, sharing ideas, stories, moral (but not technical) support, and taking an active part in the FreeBSD community. We take our problems and support questions to freebsd-questions, and use freebsd-newbies to meet others who are doing the same things that we do as newbies. &a.openoffice.name; OpenOffice.org Discussions concerning the porting and maintenance of OpenOffice.org and - StarOffice. + &staroffice;. &a.performance.name; Discussions about tuning or speeding up FreeBSD This mailing list exists to provide a place for hackers, administrators, and/or concerned parties to discuss performance related topics pertaining to FreeBSD. Acceptable topics includes talking about FreeBSD installations that are either under high load, are experiencing performance problems, or are pushing the limits of FreeBSD. Concerned parties that are willing to work toward improving the performance of FreeBSD are highly encouraged to subscribe to this list. This is a highly technical list ideally suited for experienced FreeBSD users, hackers, or administrators interested in keeping FreeBSD fast, robust, and scalable. This list is not a question-and-answer list that replaces reading through documentation, but it is a place to make contributions or inquire about unanswered performance related topics. &a.platforms.name; Porting to Non Intel platforms Cross-platform FreeBSD issues, general discussion and proposals for non Intel FreeBSD ports. This is a technical mailing list for which strictly technical content is expected. &a.policy.name; Core team policy decisions This is a low volume, read-only mailing list for FreeBSD Core Team Policy decisions. &a.ports.name; Discussion of ports Discussions concerning FreeBSD's ports collection (/usr/ports), ports infrastructure, and general ports coordination efforts. This is a technical mailing list for which strictly technical content is expected. &a.ports-bugs.name; Discussion of ports bugs Discussions concerning problem reports for FreeBSD's ports collection (/usr/ports), proposed ports, or modifications to ports. This is a technical mailing list for which strictly technical content is expected. &a.questions.name; User questions This is the mailing list for questions about FreeBSD. You should not send how to questions to the technical lists unless you consider the question to be pretty technical. &a.scsi.name; SCSI subsystem This is the mailing list for people working on the SCSI subsystem for FreeBSD. This is a technical mailing list for which strictly technical content is expected. &a.security.name; Security issues FreeBSD computer security issues (DES, Kerberos, known security holes and fixes, etc). This is a technical mailing list for which strictly technical discussion is expected. Note that this is not a question-and-answer list, but that contributions (BOTH question AND answer) to the FAQ are welcome. &a.security-notifications.name; Security Notifications Notifications of FreeBSD security problems and fixes. This is not a discussion list. The discussion list is FreeBSD-security. &a.small.name; Using FreeBSD in embedded applications This list discusses topics related to unusually small and embedded FreeBSD installations. This is a technical mailing list for which strictly technical content is expected. &a.stable.name; Discussions about the use of &os.stable; This is the mailing list for users of &os.stable;. It includes warnings about new features coming out in -STABLE that will affect the users, and instructions on steps that must be taken to remain -STABLE. Anyone running STABLE should subscribe to this list. This is a technical mailing list for which strictly technical content is expected. &a.standards.name; C99 & POSIX Conformance This is a forum for technical discussions related to FreeBSD Conformance to the C99 and the POSIX standards. &a.usergroups.name; User Group Coordination List This is the mailing list for the coordinators from each of the local area Users Groups to discuss matters with each other and a designated individual from the Core Team. This mail list should be limited to meeting synopsis and coordination of projects that span User Groups. &a.vendors.name; Vendors Coordination discussions between The FreeBSD Project and Vendors of software and hardware for FreeBSD. Filtering on the Mailing Lists The &os; mailing lists are filtered in multiple ways to avoid the distribution of spam, viruses, and other unwanted emails. The filtering actions described in this section do not include all those used to protect the mailing lists. Only certain types of attachments are allowed on the mailing lists. All attachments with a MIME content type not found in the list below will be stripped before an email is distributed on the mailing lists. application/octet-stream application/pdf application/pgp-signature application/x-pkcs7-signature message/rfc822 multipart/alternative multipart/related multipart/signed text/html text/plain text/x-diff text/x-patch Some of the mailing lists might allow attachments of other MIME content types, but the above list should be applicable for most of the mailing lists. If an email contains both an HTML and a plain text version, the HTML version will be removed. If an email contains only an HTML version, it will be converted to plain text. Usenet Newsgroups In addition to two FreeBSD specific newsgroups, there are many others in which FreeBSD is discussed or are otherwise relevant to FreeBSD users. Keyword searchable archives are available for some of these newsgroups from courtesy of Warren Toomey wkt@cs.adfa.edu.au. BSD Specific Newsgroups comp.unix.bsd.freebsd.announce comp.unix.bsd.freebsd.misc de.comp.os.unix.bsd (German) fr.comp.os.bsd (French) Other &unix; Newsgroups of Interest comp.unix comp.unix.questions comp.unix.admin comp.unix.programmer comp.unix.shell comp.unix.user-friendly comp.security.unix comp.sources.unix comp.unix.advocacy comp.unix.misc comp.bugs.4bsd comp.bugs.4bsd.ucb-fixes comp.unix.bsd X Window System comp.windows.x.i386unix comp.windows.x comp.windows.x.apps comp.windows.x.announce comp.windows.x.intrinsics comp.windows.x.motif comp.windows.x.pex comp.emulators.ms-windows.wine World Wide Web Servers — Central Server. — IPv6 Austria. — IPv6 Denmark. — IPv6 Germany. — IPv6 (6bone) Japan. — IPv6 Norway. — IPv6 UK. — IPv6 USA/1. — IPv6 USA/2. — Argentina. — Australia/1. — Australia/2. — Austria/1. — Austria/2. — Belgium. — Brazil/1. — Brazil/2. — Brazil/3. — Bulgaria. — Canada/1. — Canada/2. — China. — Czech Republic. — Denmark/1. — Denmark/2. — Estonia. — Finland/1. — Finland/2. — France. — Germany/1. — Germany/2. — Germany/3. — Greece/1. — Greece/2. — Hong Kong. — Hungary/1. — Hungary/2. — Iceland. — Ireland/1. — Ireland/2. — Italy/1. — Italy/2. — Japan. — Korea/1. — Korea/2. — Korea/3. — Latvia. — Lithuania. — Netherlands/1. — Netherlands/2. — New Zealand. — Norway/1. — Norway/2. — Philippines. — Poland/1. — Poland/2. — Portugal/1. — Portugal/2. — Portugal/3. — Romania/1. — Romania/2. — Romania/3. — Romania/4. — Russia/1. — Russia/2. — Russia/3. — Russia/4. — San Marino. — Singapore. — Slovak Republic/1. — Slovak Republic/2. — Slovenia/1. — Slovenia/2. — Spain/1. — Spain/2. — Spain/3. — South Africa/1. — South Africa/2. — Sweden/1. — Sweden/2. — Switzerland/1. — Switzerland/2. — Taiwan/1. — Taiwan/2. — Taiwan/3. — Taiwan/4. — Turkey/1. — Turkey/2. — Turkey/3. — Ukraine/1. — Ukraine/2. — Ukraine/3. — Ukraine/Crimea. — United Kingdom/1. — United Kingdom/2. — United Kingdom/3. — United Kingdom/4. — United Kingdom/5. — USA/1. — USA/2. — USA/3. Email Addresses The following user groups provide FreeBSD related email addresses for their members. The listed administrator reserves the right to revoke the address if it is abused in any way. Domain Facilities User Group Administrator ukug.uk.FreeBSD.org Forwarding only freebsd-users@uk.FreeBSD.org Lee Johnston lee@uk.FreeBSD.org Shell Accounts The following user groups provide shell accounts for people who are actively supporting the FreeBSD project. The listed administrator reserves the right to cancel the account if it is abused in any way. Host Access Facilities Administrator storm.uk.FreeBSD.org SSH only Read-only cvs, personal web space, email &a.brian; dogma.freebsd-uk.eu.org Telnet/FTP/SSH Email, Web space, Anonymous FTP Lee Johnston lee@uk.FreeBSD.org diff --git a/en_US.ISO8859-1/books/handbook/kernelconfig/chapter.sgml b/en_US.ISO8859-1/books/handbook/kernelconfig/chapter.sgml index b03031957e..d8ece4c62b 100644 --- a/en_US.ISO8859-1/books/handbook/kernelconfig/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/kernelconfig/chapter.sgml @@ -1,1553 +1,1553 @@ Jim Mock Updated and restructured by Jake Hamby Originally contributed by Configuring the FreeBSD Kernel Synopsis kernel building a custom kernel The kernel is the core of the &os; operating system. It is responsible for managing memory, enforcing security controls, networking, disk access, and much more. While more and more of &os; becomes dynamically configurable it is still occasionally necessary to reconfigure and recompile your kernel. After reading this chapter, you will know: Why you might need to build a custom kernel. How to write a kernel configuration file, or alter an existing configuration file. How to use the kernel configuration file to create and build a new kernel. How to install the new kernel. How to create any entries in /dev that may be required. How to troubleshoot if things go wrong. Why Build a Custom Kernel? Traditionally, &os; has had what is called a monolithic kernel. This means that the kernel was one large program, supported a fixed list of devices, and if you wanted to change the kernel's behavior then you had to compile a new kernel, and then reboot your computer with the new kernel. Today, &os; is rapidly moving to a model where much of the kernel's functionality is contained in modules which can be dynamically loaded and unloaded from the kernel as necessary. This allows the kernel to adapt to new hardware suddenly becoming available (such as PCMCIA cards in a laptop), or for new functionality to be brought into the kernel that was not necessary when the kernel was originally compiled. This is known as a modular kernel. Colloquially these are called KLDs. Despite this, it is still necessary to carry out some static kernel configuration. In some cases this is because the functionality is so tied to the kernel that it can not be made dynamically loadable. In others it may simply be because no one has yet taken the time to write a dynamic loadable kernel module for that functionality yet. Building a custom kernel is one of the most important rites of passage nearly every &unix; user must endure. This process, while time consuming, will provide many benefits to your &os; system. Unlike the GENERIC kernel, which must support a wide range of hardware, a custom kernel only contains support for your PC's hardware. This has a number of benefits, such as: Faster boot time. Since the kernel will only probe the hardware you have on your system, the time it takes your system to boot will decrease dramatically. Less memory usage. A custom kernel often uses less memory than the GENERIC kernel, which is important because the kernel must always be present in real memory. For this reason, a custom kernel is especially useful on a system with a small amount of RAM. Additional hardware support. A custom kernel allows you to add in support for devices such as sound cards, which are not present in the GENERIC kernel. Building and Installing a Custom Kernel kernel building / installing First, let us take a quick tour of the kernel build directory. All directories mentioned will be relative to the main /usr/src/sys directory, which is also accessible through /sys. There are a number of subdirectories here representing different parts of the kernel, but the most important, for our purposes, are arch/conf, where you will edit your custom kernel configuration, and compile, which is the staging area where your kernel will be built. arch represents either i386, alpha, or pc98 (an alternative development branch of PC hardware, popular in Japan). Everything inside a particular architecture's directory deals with that architecture only; the rest of the code is common to all platforms to which &os; could potentially be ported. Notice the logical organization of the directory structure, with each supported device, file system, and option in its own subdirectory. &os; 5.X and up has support for sparc64, and a few other architectures under development. If there is not a /usr/src/sys directory on your system, then the kernel source has not been installed. The easiest way to do this is by running /stand/sysinstall as root, choosing Configure, then Distributions, then src, then sys. If you have an aversion to sysinstall and you have access to an official &os; CDROM, then you can also install the source from the command line: &prompt.root; mount /cdrom &prompt.root; mkdir -p /usr/src/sys &prompt.root; ln -s /usr/src/sys /sys &prompt.root; cat /cdrom/src/ssys.[a-d]* | tar -xzvf - Next, move to the arch/conf directory and copy the GENERIC configuration file to the name you want to give your kernel. For example: &prompt.root; cd /usr/src/sys/i386/conf &prompt.root; cp GENERIC MYKERNEL Traditionally, this name is in all capital letters and, if you are maintaining multiple &os; machines with different hardware, it is a good idea to name it after your machine's hostname. We will call it MYKERNEL for the purpose of this example. Storing your kernel config file directly under /usr/src can be a bad idea. If you are experiencing problems it can be tempting to just delete /usr/src and start again. Five seconds after you do that you realize that you have deleted your custom kernel config file. Do not edit GENERIC directly, as it may get overwritten the next time you update your source tree, and your kernel modifications will be lost. You might want to keep your kernel config file elsewhere, and then create a symbolic link to the file in the i386 directory. For example: &prompt.root; cd /usr/src/sys/i386/conf &prompt.root; mkdir /root/kernels &prompt.root; cp GENERIC /root/kernels/MYKERNEL &prompt.root; ln -s /root/kernels/MYKERNEL You must execute these and all of the following commands under the root account or you will get permission denied errors. Now, edit MYKERNEL with your favorite text editor. If you are just starting out, the only editor available will probably be vi, which is too complex to explain here, but is covered well in many books in the bibliography. However, &os; does offer an easier editor called ee which, if you are a beginner, should be your editor of choice. Feel free to change the comment lines at the top to reflect your configuration or the changes you have made to differentiate it from GENERIC. SunOS If you have built a kernel under &sunos; or some other BSD operating system, much of this file will be very familiar to you. If you are coming from some other operating system such as DOS, on the other hand, the GENERIC configuration file might seem overwhelming to you, so follow the descriptions in the Configuration File section slowly and carefully. Be sure to always check the file /usr/src/UPDATING, before you perform any update steps, in the case you sync your source tree with the latest sources of the &os; project. In this file all important issues with updating &os; are typed out. /usr/src/UPDATING always fits your version of the &os; source, and is therefore more accurate for new information than the handbook. You must now compile the source code for the kernel. There are two procedures you can use to do this, and the one you will use depends on why you are rebuilding the kernel, and the version of &os; you are running. If you have installed only the kernel source code, use procedure 1. If you are running a &os; version prior to 4.0, and you are not upgrading to &os; 4.0 or higher using the make world procedure, use procedure 1. If you are building a new kernel without updating the source code (perhaps just to add a new option, such as IPFIREWALL) you can use either procedure. If you are rebuilding the kernel as part of a make world process, use procedure 2. Procedure 1. Building a Kernel the <quote>Traditional</quote> Way Run &man.config.8; to generate the kernel source code. &prompt.root; /usr/sbin/config MYKERNEL Change into the build directory. This is printed out after running the aforementioned command. &prompt.root; cd ../compile/MYKERNEL For &os; version prior to 5.0, use instead: &prompt.root; cd ../../compile/MYKERNEL Compile the kernel. &prompt.root; make depend &prompt.root; make Install the new kernel. &prompt.root; make install Procedure 2. Building a Kernel the <quote>New</quote> Way Change to the /usr/src directory. &prompt.root; cd /usr/src Compile the kernel. &prompt.root; make buildkernel KERNCONF=MYKERNEL Install the new kernel. &prompt.root; make installkernel KERNCONF=MYKERNEL In &os; 4.2 and older you must replace KERNCONF= with KERNEL=. 4.2-STABLE that was fetched before Feb 2nd, 2001 does not recognize KERNCONF=. cvsup anonymous CVS CTM CVS anonymous If you have not upgraded your source tree in any way (you have not run CVSup, CTM, or used anoncvs), then you should use the config, make depend, make, make install sequence. kernel.old The new kernel will be copied to the root directory as /kernel and the old kernel will be moved to /kernel.old. Now, shutdown the system and reboot to use your new kernel. In case something goes wrong, there are some troubleshooting instructions at the end of this chapter. Be sure to read the section which explains how to recover in case your new kernel does not boot. As of &os; 5.0, kernels are installed along with their modules in /boot/kernel, and old kernels will be backed up in /boot/kernel.old. Other files relating to the boot process, such as the boot &man.loader.8; and configuration are also stored in /boot. Third party or custom modules may be placed in /boot/modules, although users should be aware that keeping modules in sync with the compiled kernel is very important. Modules not intended to run with the compiled kernel may result in instability or incorrectness. If you have added any new devices (such as sound cards) and you are running &os; 4.X or previous versions, you may have to add some device nodes to your /dev directory before you can use them. For more information, take a look at Making Device Nodes section later on in this chapter. The Configuration File kernel LINT LINT kernel config file The general format of a configuration file is quite simple. Each line contains a keyword and one or more arguments. For simplicity, most lines only contain one argument. Anything following a # is considered a comment and ignored. The following sections describe each keyword, generally in the order they are listed in GENERIC, although some related keywords have been grouped together in a single section (such as Networking) even though they are actually scattered throughout the GENERIC file. An exhaustive list of options and more detailed explanations of the device lines is present in the LINT configuration file, located in the same directory as GENERIC. If you are in doubt as to the purpose or necessity of a line, check first in LINT. In &os; 5.X and above the LINT is non-existent. See the NOTES file for architecture dependent options. Some options, mainly architecture independent ones, are stored in the /usr/src/sys/conf/NOTES file. It's advisable to review the options in here also. kernel example config file The following is an example GENERIC kernel configuration file with various additional comments where needed for clarity. This example should match your copy in /usr/src/sys/i386/conf/GENERIC fairly closely. For details of all the possible kernel options, see /usr/src/sys/i386/conf/LINT. # # GENERIC -- Generic kernel configuration file for &os;/i386 # # For more information on this file, please read the handbook section on # Kernel Configuration Files: # # http://www.&os;.org/doc/en_US.ISO8859-1/books/handbook/kernelconfig-config.html # # The handbook is also available locally in /usr/share/doc/handbook # if you've installed the doc distribution, otherwise always see the # &os; World Wide Web server (http://www.FreeBSD.org/) for the # latest information. # # An exhaustive list of options and more detailed explanations of the # device lines is also present in the ../../conf/NOTES and NOTES files. # If you are in doubt as to the purpose or necessity of a line, check first # in NOTES. # # $FreeBSD: src/sys/i386/conf/GENERIC,v 1.380 2003/03/29 13:36:41 mdodd Exp $ The following are the mandatory keywords required in every kernel you build: kernel options machine machine i386 This is the machine architecture. It must be either i386, pc98, sparc64, alpha, ia64, amd64, or powerpc. kernel options cpu cpu I486_CPU cpu I586_CPU cpu I686_CPU The above option specifies the type of CPU you have in your system. You may have multiple instances of the CPU line (i.e., you are not sure whether you should use I586_CPU or I686_CPU), however, for a custom kernel, it is best to specify only the CPU you have. If you are unsure of your CPU type, you can check the /var/run/dmesg.boot file to view your boot up messages. kernel options cpu type Support for I386_CPU is still provided in the source of &os;, but it is disabled by default in both -STABLE and -CURRENT. This means that to install &os; with a 386-class cpu, you now have the following options: Install an older &os; release and rebuild from source as described in . Build the userland and kernel on a newer machine and install on the 386 using the precompiled /usr/obj files (see for details). Roll your own release of FreeBSD which includes I386_CPU support in the kernels of the installation CD-ROM. The first of these options is probably the easiest of all, but you will need a lot of disk space on a 386-class machine which may be difficult to find. kernel options ident ident GENERIC This is the identification of the kernel. You should change this to whatever you named your kernel, i.e. MYKERNEL if you have followed the instructions of the previous examples. The value you put in the ident string will print when you boot up the kernel, so it is useful to give the new kernel a different name if you want to keep it separate from your usual kernel (i.e. you want to build an experimental kernel). kernel options maxusers maxusers n The maxusers option sets the size of a number of important system tables. This number is supposed to be roughly equal to the number of simultaneous users you expect to have on your machine. Starting with &os; 4.5, the system will auto-tune this setting for you if you explicitly set it to 0 The auto-tuning algorithm sets maxuser equal to the amount of memory in the system, with a minimum of 32, and a maximum of 384.. In &os; 5.X, maxusers will default to 0 if not specified. If you are using an version of &os; earlier than 4.5, or you want to manage it yourself you will want to set maxusers to at least 4, especially if you are using the X Window System or compiling software. The reason is that the most important table set by maxusers is the maximum number of processes, which is set to 20 + 16 * maxusers, so if you set maxusers to 1, then you can only have 36 simultaneous processes, including the 18 or so that the system starts up at boot time, and the 15 or so you will probably create when you start the X Window System. Even a simple task like reading a manual page will start up nine processes to filter, decompress, and view it. Setting maxusers to 64 will allow you to have up to 1044 simultaneous processes, which should be enough for nearly all uses. If, however, you see the dreaded proc table full error when trying to start another program, or are running a server with a large number of simultaneous users (like ftp.FreeBSD.org), you can always increase the number and rebuild. maxusers does not limit the number of users which can log into your machine. It simply sets various table sizes to reasonable values considering the maximum number of users you will likely have on your system and how many processes each of them will be running. One keyword which does limit the number of simultaneous remote logins and X terminal windows is pseudo-device pty 16. # Floating point support - do not disable. device npx0 at nexus? port IO_NPX irq 13 npx0 is the interface to the floating point math unit in &os;, which is either the hardware co-processor or the software math emulator. This is not optional. # Pseudo devices - the number indicates how many units to allocate. pseudo-device loop # Network loopback This is the generic loopback device for TCP/IP. If you telnet or FTP to localhost (a.k.a., 127.0.0.1) it will come back at you through this pseudo-device. This is mandatory. Everything that follows is more or less optional. See the notes underneath or next to each option for more information. #To statically compile in device wiring instead of /boot/device.hints #hints "GENERIC.hints" #Default places to look for devices. In &os; 5.X and newer versions the &man.device.hints.5; is used to configure options of the device drivers. The default location that &man.loader.8; will check at boot time is /boot/device.hints. Using the hints option you can compile these hints statically into your kernel. Then there is no need to create a device.hints file in /boot. #makeoptions DEBUG=-g #Build kernel with gdb(1) debug symbols The normal build process of the &os; does not include debugging information when building the kernel and strips most symbols after the resulting kernel is linked, to save some space at the install location. If you are going to do tests of kernels in the -CURRENT branch or develop changes of your own for the &os; kernel, you might want to uncomment this line. It will enable the use of the option which enables debugging information when passed to &man.gcc.1;. The same can be accomplished by the &man.config.8; option, if you are using the traditional way for building your kernels (See the for more informations.). options MATH_EMULATE #Support for x87 emulation This line allows the kernel to simulate a math co-processor if your computer does not have one (386 or 486SX). If you have a 486DX, or a 386 or 486SX (with a separate 387 or 487 chip), or higher (&pentium;, &pentium; II, etc.), you can comment this line out. The normal math co-processor emulation routines that come with &os; are not very accurate. If you do not have a math co-processor, and you need the best accuracy, it is recommended that you change this option to GPL_MATH_EMULATE to use the GNU math support, which is not included by default for licensing reasons. In &os; 5.X, math emulation is disabled by default, as older CPUs that do not have native floating point math support are far less common, and in many cases not supported by the GENERIC kernel without other additional options. options INET #InterNETworking Networking support. Leave this in, even if you do not plan to be connected to a network. Most programs require at least loopback networking (i.e., making network connections within your PC), so this is essentially mandatory. options INET6 #IPv6 communications protocols This enables the IPv6 communication protocols. options FFS #Berkeley Fast Filesystem options FFS_ROOT #FFS usable as root device [keep this!] This is the basic hard drive Filesystem. Leave it in if you boot from the hard disk. In &os; 5.X, FFS_ROOT is no longer required. options UFS_ACL #Support for access control lists This option, present only in &os; 5.X, enables kernel support for access control lists. This relies on the use of extended attributes and UFS2, and the feature is described in detail in the . ACLs are enabled by default, and should not be disabled in the kernel if they have been used previously on a file system, as this will remove the access control lists changing the way files are protected in unpredictable ways. options UFS_DIRHASH #Improve performance on big directories This option includes functionality to speed up disk operations on large directories, at the expense of using additional memory. You would normally keep this for a large server, or interactive workstation, and remove it if you are using &os; on a smaller system where memory is at a premium and disk access speed is less important, such as a firewall. options SOFTUPDATES #Enable FFS Soft Updates support This option enables Soft Updates in the kernel, this will help speed up write access on the disks. Even when this functionality is provided by the kernel, it must be turned on for specific disks. Review the output from &man.mount.8; to see if Soft Updates is enabled for your system disks. If you do not see the soft-updates option then you will need to activate it using the &man.tunefs.8; (for existing filesystems) or &man.newfs.8; (for new filesystems) commands. options MFS #Memory Filesystem options MD_ROOT #MD is a potential root device This is the memory-mapped Filesystem. This is basically a RAM disk for fast storage of temporary files, useful if you have a lot of swap space that you want to take advantage of. A perfect place to mount an MFS partition is on the /tmp directory, since many programs store temporary data here. To mount an MFS RAM disk on /tmp, add the following line to /etc/fstab: /dev/ad1s2b /tmp mfs rw 0 0 Now you simply need to either reboot, or run the command mount /tmp. In &os; 5.X, &man.md.4;-backed UFS file systems are used for memory file systems rather than MFS. Information on configuring memory-backed file systems may be found in the manual pages for &man.mdconfig.8; and &man.mdmfs.8;, and in . As a result, the MFS option is no longer supported. kernel options NFS kernel options NFS_ROOT options NFS #Network Filesystem options NFS_ROOT #NFS usable as root device, NFS required The network Filesystem. Unless you plan to mount partitions from a &unix; file server over TCP/IP, you can comment these out. kernel options MSDOSFS options MSDOSFS #MSDOS Filesystem The &ms-dos; Filesystem. Unless you plan to mount a DOS formatted hard drive partition at boot time, you can safely comment this out. It will be automatically loaded the first time you mount a DOS partition, as described above. Also, the excellent mtools software (in the ports collection) allows you to access DOS floppies without having to mount and unmount them (and does not require MSDOSFS at all). options CD9660 #ISO 9660 Filesystem options CD9660_ROOT #CD-ROM usable as root, CD9660 required The ISO 9660 Filesystem for CDROMs. Comment it out if you do not have a CDROM drive or only mount data CDs occasionally (since it will be dynamically loaded the first time you mount a data CD). Audio CDs do not need this Filesystem. options PROCFS #Process filesystem The process filesystem. This is a pretend filesystem mounted on /proc which allows programs like &man.ps.1; to give you more information on what processes are running. In &os; 5.X, use of PROCFS is not required under most circumstances, as most debugging and monitoring tools have been adapted to run without PROCFS. In addition, 5.X-CURRENT kernels making use of PROCFS must now also include support for PSEUDOFS: options PSEUDOFS #Pseudo-filesystem framework PSEUDOFS is not available in &os; 4.X. Unlike in &os; 4.X, new installations of &os; 5.X will not mount the process file system by default. options COMPAT_43 #Compatible with BSD 4.3 [KEEP THIS!] Compatibility with 4.3BSD. Leave this in; some programs will act strangely if you comment this out. options COMPAT_FREEBSD4 #Compatible with &os;4 This option is required on &os; 5.X &i386; and Alpha systems to support applications compiled on older versions of &os; that use older system call interfaces. It is recommended that this option be used on all &i386; and Alpha systems that may run older applications; platforms that gained support only in 5.X, such as ia64 and &sparc64;, do not require this option. options SCSI_DELAY=15000 #Delay (in ms) before probing SCSI This causes the kernel to pause for 15 seconds before probing each SCSI device in your system. If you only have IDE hard drives, you can ignore this, otherwise you will probably want to lower this number, perhaps to 5 seconds, to speed up booting. Of course, if you do this, and &os; has trouble recognizing your SCSI devices, you will have to raise it back up. options UCONSOLE #Allow users to grab the console Allow users to grab the console, which is useful for X users. For example, you can create a console xterm by typing xterm -C, which will display any &man.write.1;, &man.talk.1;, and any other messages you receive, as well as any console messages sent by the kernel. In &os; 5.X, UCONSOLE is no longer required. options USERCONFIG #boot -c editor This option allows you to boot the configuration editor from the boot menu. options VISUAL_USERCONFIG #visual boot -c editor This option allows you to boot the visual configuration editor from the boot menu. From &os; versions 5.0 and later, the USERCONFIG options has been depreciated in favor of the new &man.device.hints.5; method. For more information on &man.device.hints.5; please visit . options KTRACE #ktrace(1) support This enables kernel process tracing, which is useful in debugging. options SYSVSHM #SYSV-style shared memory This option provides for System V shared memory. The most common use of this is the XSHM extension in X, which many graphics-intensive programs will automatically take advantage of for extra speed. If you use X, you will definitely want to include this. options SYSVSEM #SYSV-style semaphores Support for System V semaphores. Less commonly used but only adds a few hundred bytes to the kernel. options SYSVMSG #SYSV-style message queues Support for System V messages. Again, only adds a few hundred bytes to the kernel. The &man.ipcs.1; command will list any processes using each of these System V facilities. options P1003_1B #Posix P1003_1B real-time extensions options _KPOSIX_PRIORITY_SCHEDULING Real-time extensions added in the 1993 &posix;. Certain applications in the ports collection use these - (such as StarOffice). + (such as &staroffice;). In &os; 5.X, all of this functionality is now provided by the _KPOSIX_PRIORITY_SCHEDULING option, and P1003_1B is no longer required. kernel options ICMP_BANDLIM Denial of Service (DoS) options ICMP_BANDLIM #Rate limit bad replies This option enables ICMP error response bandwidth limiting. You typically want this option as it will help protect the machine from denial of service packet attacks. In &os; 5.X, this feature is enabled by default and the ICMP_BANDLIM option is not required. kernel options SMP # To make an SMP kernel, the next two are needed #options SMP # Symmetric MultiProcessor Kernel #options APIC_IO # Symmetric (APIC) I/O The above are both required for SMP support. device isa All PCs supported by &os; have one of these. If you have an IBM PS/2 (Micro Channel Architecture), &os; provides some limited support at this time. For more information about the MCA support, see /usr/src/sys/i386/conf/LINT. device eisa Include this if you have an EISA motherboard. This enables auto-detection and configuration support for all devices on the EISA bus. device pci Include this if you have a PCI motherboard. This enables auto-detection of PCI cards and gatewaying from the PCI to ISA bus. device agp Include this if you have an AGP card in the system. This will enable support for AGP, and AGP GART for boards which have these features. # Floppy drives device fdc0 at isa? port IO_FD1 irq 6 drq 2 device fd0 at fdc0 drive 0 device fd1 at fdc0 drive 1 This is the floppy drive controller. fd0 is the A: floppy drive, and fd1 is the B: drive. device ata This driver supports all ATA and ATAPI devices. You only need one device ata line for the kernel to detect all PCI ATA/ATAPI devices on modern machines. device atadisk # ATA disk drives This is needed along with device ata for ATA disk drives. device atapicd # ATAPI CDROM drives This is needed along with device ata for ATAPI CDROM drives. device atapifd # ATAPI floppy drives This is needed along with device ata for ATAPI floppy drives. device atapist # ATAPI tape drives This is needed along with device ata for ATAPI tape drives. options ATA_STATIC_ID #Static device numbering This makes the controller number static (like the old driver) or else the device numbers are dynamically allocated. # ATA and ATAPI devices device ata0 at isa? port IO_WD1 irq 14 device ata1 at isa? port IO_WD2 irq 15 Use the above for older, non-PCI systems. # SCSI Controllers device ahb # EISA AHA1742 family device ahc # AHA2940 and onboard AIC7xxx devices device amd # AMD 53C974 (Teckram DC-390(T)) device dpt # DPT Smartcache - See LINT for options! device isp # Qlogic family device ncr # NCR/Symbios Logic device sym # NCR/Symbios Logic (newer chipsets) device adv0 at isa? device adw device bt0 at isa? device aha0 at isa? device aic0 at isa? SCSI controllers. Comment out any you do not have in your system. If you have an IDE only system, you can remove these altogether. # SCSI peripherals device scbus # SCSI bus (required) device da # Direct Access (disks) device sa # Sequential Access (tape etc) device cd # CD device pass # Passthrough device (direct SCSI access) SCSI peripherals. Again, comment out any you do not have, or if you have only IDE hardware, you can remove them completely. # RAID controllers device ida # Compaq Smart RAID device amr # AMI MegaRAID device mlx # Mylex DAC960 family Supported RAID controllers. If you do not have any of these, you can comment them out or remove them. # atkbdc0 controls both the keyboard and the PS/2 mouse device atkbdc0 at isa? port IO_KBD The keyboard controller (atkbdc) provides I/O services for the AT keyboard and PS/2 style pointing devices. This controller is required by the keyboard driver (atkbd) and the PS/2 pointing device driver (psm). device atkbd0 at atkbdc? irq 1 The atkbd driver, together with atkbdc controller, provides access to the AT 84 keyboard or the AT enhanced keyboard which is connected to the AT keyboard controller. device psm0 at atkbdc? irq 12 Use this device if your mouse plugs into the PS/2 mouse port. device vga0 at isa? The video card driver. # splash screen/screen saver pseudo-device splash Splash screen at start up! Screen savers require this too. # syscons is the default console driver, resembling an SCO console device sc0 at isa? sc0 is the default console driver, which resembles a SCO console. Since most full-screen programs access the console through a terminal database library like termcap, it should not matter whether you use this or vt0, the VT220 compatible console driver. When you log in, set your TERM variable to scoansi if full-screen programs have trouble running under this console. # Enable this and PCVT_FREEBSD for pcvt vt220 compatible console driver #device vt0 at isa? #options XSERVER # support for X server on a vt console #options FAT_CURSOR # start with block cursor # If you have a ThinkPAD, uncomment this along with the rest of the PCVT lines #options PCVT_SCANSET=2 # IBM keyboards are non-std This is a VT220-compatible console driver, backward compatible to VT100/102. It works well on some laptops which have hardware incompatibilities with sc0. Also set your TERM variable to vt100 or vt220 when you log in. This driver might also prove useful when connecting to a large number of different machines over the network, where termcap or terminfo entries for the sc0 device are often not available — vt100 should be available on virtually any platform. # Power management support (see LINT for more options) device apm0 at nexus? disable flags 0x20 # Advanced Power Management Advanced Power Management support. Useful for laptops. # PCCARD (PCMCIA) support device card device pcic0 at isa? irq 10 port 0x3e0 iomem 0xd0000 device pcic1 at isa? irq 11 port 0x3e2 iomem 0xd4000 disable PCMCIA support. You want this if you are using a laptop. # Serial (COM) ports device sio0 at isa? port IO_COM1 flags 0x10 irq 4 device sio1 at isa? port IO_COM2 irq 3 device sio2 at isa? disable port IO_COM3 irq 5 device sio3 at isa? disable port IO_COM4 irq 9 These are the four serial ports referred to as COM1 through COM4 in the &ms-dos/&windows; world. If you have an internal modem on COM4 and a serial port at COM2, you will have to change the IRQ of the modem to 2 (for obscure technical reasons, IRQ2 = IRQ 9) in order to access it from &os;. If you have a multiport serial card, check the manual page for &man.sio.4; for more information on the proper values for these lines. Some video cards (notably those based on S3 chips) use IO addresses in the form of 0x*2e8, and since many cheap serial cards do not fully decode the 16-bit IO address space, they clash with these cards making the COM4 port practically unavailable. Each serial port is required to have a unique IRQ (unless you are using one of the multiport cards where shared interrupts are supported), so the default IRQs for COM3 and COM4 cannot be used. # Parallel port device ppc0 at isa? irq 7 This is the ISA-bus parallel port interface. device ppbus # Parallel port bus (required) Provides support for the parallel port bus. device lpt # Printer Support for parallel port printers. All three of the above are required to enable parallel printer support. device plip # TCP/IP over parallel This is the driver for the parallel network interface. device ppi # Parallel port interface device The general-purpose I/O (geek port) + IEEE1284 I/O. #device vpo # Requires scbus and da zip drive This is for an Iomega Zip drive. It requires scbus and da support. Best performance is achieved with ports in EPP 1.9 mode. # PCI Ethernet NICs. device de # DEC/Intel DC21x4x (Tulip) device fxp # Intel EtherExpress PRO/100B (82557, 82558) device tx # SMC 9432TX (83c170 EPIC) device vx # 3Com 3c590, 3c595 (Vortex) device wx # Intel Gigabit Ethernet Card (Wiseman) Various PCI network card drivers. Comment out or remove any of these not present in your system. # PCI Ethernet NICs that use the common MII bus controller code. device miibus # MII bus support MII bus support is required for some PCI 10/100 Ethernet NICs, namely those which use MII-compliant transceivers or implement transceiver control interfaces that operate like an MII. Adding device miibus to the kernel config pulls in support for the generic miibus API and all of the PHY drivers, including a generic one for PHYs that are not specifically handled by an individual driver. device dc # DEC/Intel 21143 and various workalikes device rl # RealTek 8129/8139 device sf # Adaptec AIC-6915 (Starfire) device sis # Silicon Integrated Systems SiS 900/SiS 7016 device ste # Sundance ST201 (D-Link DFE-550TX) device tl # Texas Instruments ThunderLAN device vr # VIA Rhine, Rhine II device wb # Winbond W89C840F device xl # 3Com 3c90x (Boomerang, Cyclone) Drivers that use the MII bus controller code. # ISA Ethernet NICs. device ed0 at isa? port 0x280 irq 10 iomem 0xd8000 device ex device ep # WaveLAN/IEEE 802.11 wireless NICs. Note: the WaveLAN/IEEE really # exists only as a PCMCIA device, so there is no ISA attachment needed # and resources will always be dynamically assigned by the pccard code. device wi # Aironet 4500/4800 802.11 wireless NICs. Note: the declaration below will # work for PCMCIA and PCI cards, as well as ISA cards set to ISA PnP # mode (the factory default). If you set the switches on your ISA # card for a manually chosen I/O address and IRQ, you must specify # those parameters here. device an # The probe order of these is presently determined by i386/isa/isa_compat.c. device ie0 at isa? port 0x300 irq 10 iomem 0xd0000 device fe0 at isa? port 0x300 device le0 at isa? port 0x300 irq 5 iomem 0xd0000 device lnc0 at isa? port 0x280 irq 10 drq 0 device cs0 at isa? port 0x300 device sn0 at isa? port 0x300 irq 10 # requires PCCARD (PCMCIA) support to be activated #device xe0 at isa? ISA Ethernet drivers. See /usr/src/sys/i386/conf/LINT for which cards are supported by which driver. pseudo-device ether # Ethernet support ether is only needed if you have an Ethernet card. It includes generic Ethernet protocol code. pseudo-device sl 1 # Kernel SLIP sl is for SLIP support. This has been almost entirely supplanted by PPP, which is easier to set up, better suited for modem-to-modem connection, and more powerful. The number after sl specifies how many simultaneous SLIP sessions to support. pseudo-device ppp 1 # Kernel PPP This is for kernel PPP support for dial-up connections. There is also a version of PPP implemented as a userland application that uses tun and offers more flexibility and features such as demand dialing. The number after ppp specifies how many simultaneous PPP connections to support. pseudo-device tun # Packet tunnel. This is used by the userland PPP software. A number after tun specifies the number of simultaneous PPP sessions to support. See the PPP section of this book for more information. pseudo-device pty # Pseudo-ttys (telnet etc) This is a pseudo-terminal or simulated login port. It is used by incoming telnet and rlogin sessions, xterm, and some other applications such as Emacs. A number after pty indicates the number of ptys to create. If you need more than the default of 16 simultaneous xterm windows and/or remote logins, be sure to increase this number accordingly, up to a maximum of 256. pseudo-device md # Memory disks Memory disk pseudo-devices. pseudo-device gif or pseudo-device gif 4 # IPv6 and IPv4 tunneling This implements IPv6 over IPv4 tunneling, IPv4 over IPv6 tunneling, IPv4 over IPv4 tunneling, and IPv6 over IPv6 tunneling. Beginning with &os; 4.4 the gif device is auto-cloning, and you should use the first example (without the number after gif). Earlier versions of &os; require the number. pseudo-device faith 1 # IPv6-to-IPv4 relaying (translation) This pseudo-device captures packets that are sent to it and diverts them to the IPv4/IPv6 translation daemon. # The `bpf' pseudo-device enables the Berkeley Packet Filter. # Be aware of the administrative consequences of enabling this! pseudo-device bpf # Berkeley packet filter This is the Berkeley Packet Filter. This pseudo-device allows network interfaces to be placed in promiscuous mode, capturing every packet on a broadcast network (e.g., an Ethernet). These packets can be captured to disk and or examined with the &man.tcpdump.1; program. The bpf pseudo-device is also used by &man.dhclient.8; to obtain the IP address of the default router (gateway) and so on. If you use DHCP, leave this uncommented. # USB support #device uhci # UHCI PCI->USB interface #device ohci # OHCI PCI->USB interface #device usb # USB Bus (required) #device ugen # Generic #device uhid # Human Interface Devices #device ukbd # Keyboard #device ulpt # Printer #device umass # Disks/Mass storage - Requires scbus and da #device ums # Mouse # USB Ethernet, requires mii #device aue # ADMtek USB ethernet #device cue # CATC USB ethernet #device kue # Kawasaki LSI USB ethernet Support for various USB devices. For more information and additional devices supported by &os;, see /usr/src/sys/i386/conf/LINT. Making Device Nodes device nodes MAKEDEV If you are running &os; 5.0 or later you can safely skip this section. These versions use &man.devfs.5; to allocate device nodes transparently for the user. Almost every device in the kernel has a corresponding node entry in the /dev directory. These nodes look like regular files, but are actually special entries into the kernel which programs use to access the device. The shell script /dev/MAKEDEV, which is executed when you first install the operating system, creates nearly all of the device nodes supported. However, it does not create all of them, so when you add support for a new device, it pays to make sure that the appropriate entries are in this directory, and if not, add them. Here is a simple example: Suppose you add the IDE CD-ROM support to the kernel. The line to add is: device acd0 This means that you should look for some entries that start with acd0 in the /dev directory, possibly followed by a letter, such as c, or preceded by the letter r, which means a raw device. It turns out that those files are not there, so you must change to the /dev directory and type: MAKEDEV &prompt.root; sh MAKEDEV acd0 When this script finishes, you will find that there are now acd0c and racd0c entries in /dev so you know that it executed correctly. For sound cards, the following command creates the appropriate entries: &prompt.root; sh MAKEDEV snd0 When creating device nodes for devices such as sound cards, if other people have access to your machine, it may be desirable to protect the devices from outside access by adding them to the /etc/fbtab file. See &man.fbtab.5; for more information. Follow this simple procedure for any other non-GENERIC devices which do not have entries. All SCSI controllers use the same set of /dev entries, so you do not need to create these. Also, network cards and SLIP/PPP pseudo-devices do not have entries in /dev at all, so you do not have to worry about these either. If Something Goes Wrong There are five categories of trouble that can occur when building a custom kernel. They are: config fails: If the &man.config.8; command fails when you give it your kernel description, you have probably made a simple error somewhere. Fortunately, &man.config.8; will print the line number that it had trouble with, so you can quickly skip to it with vi. For example, if you see: config: line 17: syntax error You can skip to the problem in vi by typing 17G in command mode. Make sure the keyword is typed correctly, by comparing it to the GENERIC kernel or another reference. make fails: If the make command fails, it usually signals an error in your kernel description, but not severe enough for &man.config.8; to catch it. Again, look over your configuration, and if you still cannot resolve the problem, send mail to the &a.questions; with your kernel configuration, and it should be diagnosed very quickly. Installing the new kernel fails: If the kernel compiled fine, but failed to install (the make install or make installkernel command failed), the first thing to check is if your system is running at securelevel 1 or higher (see &man.init.8;). The kernel installation tries to remove the immutable flag from your kernel and set the immutable flag on the new one. Since securelevel 1 or higher prevents unsetting the immutable flag for any files on the system, the kernel installation needs to be performed at securelevel 0 or lower. The kernel does not boot: If your new kernel does not boot, or fails to recognize your devices, do not panic! Fortunately, &os; has an excellent mechanism for recovering from incompatible kernels. Simply choose the kernel you want to boot from at the &os; boot loader. You can access this when the system counts down from 10. Hit any key except for the Enter key, type unload and then type boot kernel.old, or the filename of any other kernel that will boot properly. When reconfiguring a kernel, it is always a good idea to keep a kernel that is known to work on hand. After booting with a good kernel you can check over your configuration file and try to build it again. One helpful resource is the /var/log/messages file which records, among other things, all of the kernel messages from every successful boot. Also, the &man.dmesg.8; command will print the kernel messages from the current boot. If you are having trouble building a kernel, make sure to keep a GENERIC, or some other kernel that is known to work on hand as a different name that will not get erased on the next build. You cannot rely on kernel.old because when installing a new kernel, kernel.old is overwritten with the last installed kernel which may be non-functional. Also, as soon as possible, move the working kernel to the proper kernel location or commands such as &man.ps.1; will not work properly. The proper command to unlock the kernel file that make installs (in order to move another kernel back permanently) is: &prompt.root; chflags noschg /kernel If you find you cannot do this, you are probably running at a &man.securelevel.8; greater than zero. Edit kern_securelevel in /etc/rc.conf and set it to -1, then reboot. You can change it back to its previous setting when you are happy with your new kernel. And, if you want to lock your new kernel into place, or any file for that matter, so that it cannot be moved or tampered with: &prompt.root; chflags schg /kernel In &os; 5.X, kernels are not installed with the system immutable flag, so this is unlikely to be the source of the problem you are experiencing. The kernel works, but &man.ps.1; does not work any more: If you have installed a different version of the kernel from the one that the system utilities have been built with, for example, a 4.X kernel on a 3.X system, many system-status commands like &man.ps.1; and &man.vmstat.8; will not work any more. You must recompile the libkvm library as well as these utilities. This is one reason it is not normally a good idea to use a different version of the kernel from the rest of the operating system.