diff --git a/en_US.ISO8859-1/books/handbook/disks/chapter.sgml b/en_US.ISO8859-1/books/handbook/disks/chapter.sgml index e1fae5ae49..e100733275 100644 --- a/en_US.ISO8859-1/books/handbook/disks/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/disks/chapter.sgml @@ -1,3580 +1,3580 @@ Storage Synopsis This chapter covers the use of disks in FreeBSD. This includes memory-backed disks, network-attached disks, and standard SCSI/IDE storage devices. After reading this chapter, you will know: The terminology FreeBSD uses to describe the organization of data on a physical disk (partitions and slices). How to add additional hard disks to your system. How to set up virtual file systems, such as memory disks. How to use quotas to limit disk space usage. How to encrypt disks to secure them against attackers. How to create and burn CDs and DVDs on FreeBSD. The various storage media options for backups. How to use backup programs available under FreeBSD. How to backup to floppy disks. What snapshots are and how to use them efficiently. Device Names The following is a list of physical storage devices supported in FreeBSD, and the device names associated with them. Physical Disk Naming Conventions Drive type Drive device name IDE hard drives ad IDE CDROM drives acd SCSI hard drives and USB Mass storage devices da SCSI CDROM drives cd Assorted non-standard CDROM drives mcd for Mitsumi CD-ROM, scd for Sony CD-ROM, matcd for Matsushita/Panasonic CD-ROM The &man.matcd.4; driver has been removed in FreeBSD 4.X branch since October 5th, 2002 and does not exist in FreeBSD 5.0 and 5.1 releases. However this driver is back in the FreeBSD 5.X branch since June 16th, 2003. Floppy drives fd SCSI tape drives sa IDE tape drives ast Flash drives fla for &diskonchip; Flash device RAID drives aacd for &adaptec; AdvancedRAID, mlxd and mlyd for &mylex;, amrd for AMI &megaraid;, idad for Compaq Smart RAID, twed for &tm.3ware; RAID.
David O'Brien Originally contributed by Adding Disks disks adding Lets say we want to add a new SCSI disk to a machine that currently only has a single drive. First turn off the computer and install the drive in the computer following the instructions of the computer, controller, and drive manufacturer. Due to the wide variations of procedures to do this, the details are beyond the scope of this document. Login as user root. After you have installed the drive, inspect /var/run/dmesg.boot to ensure the new disk was found. Continuing with our example, the newly added drive will be da1 and we want to mount it on /1 (if you are adding an IDE drive, the device name will be wd1 in pre-4.0 systems, or ad1 in most 4.X systems). partitions slices fdisk Because FreeBSD runs on IBM-PC compatible computers, it must take into account the PC BIOS partitions. These are different from the traditional BSD partitions. A PC disk has up to four BIOS partition entries. If the disk is going to be truly dedicated to FreeBSD, you can use the dedicated mode. Otherwise, FreeBSD will have to live within one of the PC BIOS partitions. FreeBSD calls the PC BIOS partitions slices so as not to confuse them with traditional BSD partitions. You may also use slices on a disk that is dedicated to FreeBSD, but used in a computer that also has another operating system installed. This is to not confuse the fdisk utility of the other operating system. In the slice case the drive will be added as /dev/da1s1e. This is read as: SCSI disk, unit number 1 (second SCSI disk), slice 1 (PC BIOS partition 1), and e BSD partition. In the dedicated case, the drive will be added simply as /dev/da1e. Using &man.sysinstall.8; sysinstall adding disks su Navigating <application>Sysinstall</application> You may use /stand/sysinstall to partition and label a new disk using its easy to use menus. Either login as user root or use the su command. Run /stand/sysinstall and enter the Configure menu. Within the FreeBSD Configuration Menu, scroll down and select the Fdisk option. <application>fdisk</application> Partition Editor Once inside fdisk, we can type A to use the entire disk for FreeBSD. When asked if you want to remain cooperative with any future possible operating systems, answer YES. Write the changes to the disk using W. Now exit the FDISK editor by typing q. Next you will be asked about the Master Boot Record. Since you are adding a disk to an already running system, choose None. Disk Label Editor BSD partitions Next, you need to exit sysinstall and start it again. Follow the directions above, although this time choose the Label option. This will enter the Disk Label Editor. This is where you will create the traditional BSD partitions. A disk can have up to eight partitions, labeled a-h. A few of the partition labels have special uses. The a partition is used for the root partition (/). Thus only your system disk (e.g, the disk you boot from) should have an a partition. The b partition is used for swap partitions, and you may have many disks with swap partitions. The c partition addresses the entire disk in dedicated mode, or the entire FreeBSD slice in slice mode. The other partitions are for general use. sysinstall's Label editor favors the e partition for non-root, non-swap partitions. Within the Label editor, create a single file system by typing C. When prompted if this will be a FS (file system) or swap, choose FS and type in a mount point (e.g, /mnt). When adding a disk in post-install mode, sysinstall will not create entries in /etc/fstab for you, so the mount point you specify is not important. You are now ready to write the new label to the disk and create a file system on it. Do this by typing W. Ignore any errors from sysinstall that it could not mount the new partition. Exit the Label Editor and sysinstall completely. Finish The last step is to edit /etc/fstab to add an entry for your new disk. Using Command Line Utilities Using Slices This setup will allow your disk to work correctly with other operating systems that might be installed on your computer and will not confuse other operating systems' fdisk utilities. It is recommended to use this method for new disk installs. Only use dedicated mode if you have a good reason to do so! &prompt.root; dd if=/dev/zero of=/dev/da1 bs=1k count=1 &prompt.root; fdisk -BI da1 #Initialize your new disk &prompt.root; disklabel -B -w -r da1s1 auto #Label it. &prompt.root; disklabel -e da1s1 # Edit the disklabel just created and add any partitions. &prompt.root; mkdir -p /1 &prompt.root; newfs /dev/da1s1e # Repeat this for every partition you created. &prompt.root; mount /dev/da1s1e /1 # Mount the partition(s) &prompt.root; vi /etc/fstab # Add the appropriate entry/entries to your /etc/fstab. If you have an IDE disk, substitute ad for da. On pre-4.X systems use wd. Dedicated OS/2 If you will not be sharing the new drive with another operating system, you may use the dedicated mode. Remember this mode can confuse Microsoft operating systems; however, no damage will be done by them. IBM's &os2; however, will appropriate any partition it finds which it does not understand. &prompt.root; dd if=/dev/zero of=/dev/da1 bs=1k count=1 &prompt.root; disklabel -Brw da1 auto &prompt.root; disklabel -e da1 # create the `e' partition &prompt.root; newfs -d0 /dev/da1e &prompt.root; mkdir -p /1 &prompt.root; vi /etc/fstab # add an entry for /dev/da1e &prompt.root; mount /1 An alternate method is: &prompt.root; dd if=/dev/zero of=/dev/da1 count=2 &prompt.root; disklabel /dev/da1 | disklabel -BrR da1 /dev/stdin &prompt.root; newfs /dev/da1e &prompt.root; mkdir -p /1 &prompt.root; vi /etc/fstab # add an entry for /dev/da1e &prompt.root; mount /1 Since &os; 5.1-RELEASE, the &man.bsdlabel.8; utility replaces the old &man.disklabel.8; program. With &man.bsdlabel.8; a number of obsolete options and parameters have been retired; in the examples above the option should be removed with &man.bsdlabel.8;. For more information, please refer to the &man.bsdlabel.8; manual page. RAID Software RAID Christopher Shumway Original work by Jim Brown Revised by RAIDsoftware RAIDCCD Concatenated Disk Driver (CCD) Configuration When choosing a mass storage solution the most important factors to consider are speed, reliability, and cost. It is rare to have all three in balance; normally a fast, reliable mass storage device is expensive, and to cut back on cost either speed or reliability must be sacrificed. In designing the system described below, cost was chosen as the most important factor, followed by speed, then reliability. Data transfer speed for this system is ultimately constrained by the network. And while reliability is very important, the CCD drive described below serves online data that is already fully backed up on CD-R's and can easily be replaced. Defining your own requirements is the first step in choosing a mass storage solution. If your requirements prefer speed or reliability over cost, your solution will differ from the system described in this section. Installing the Hardware In addition to the IDE system disk, three Western Digital 30GB, 5400 RPM IDE disks form the core of the CCD disk described below providing approximately 90GB of online storage. Ideally, each IDE disk would have its own IDE controller and cable, but to minimize cost, additional IDE controllers were not used. Instead the disks were configured with jumpers so that each IDE controller has one master, and one slave. Upon reboot, the system BIOS was configured to automatically detect the disks attached. More importantly, FreeBSD detected them on reboot: ad0: 19574MB <WDC WD205BA> [39770/16/63] at ata0-master UDMA33 ad1: 29333MB <WDC WD307AA> [59598/16/63] at ata0-slave UDMA33 ad2: 29333MB <WDC WD307AA> [59598/16/63] at ata1-master UDMA33 ad3: 29333MB <WDC WD307AA> [59598/16/63] at ata1-slave UDMA33 If FreeBSD does not detect all the disks, ensure that you have jumpered them correctly. Most IDE drives also have a Cable Select jumper. This is not the jumper for the master/slave relationship. Consult the drive documentation for help in identifying the correct jumper. Next, consider how to attach them as part of the file system. You should research both &man.vinum.8; () and &man.ccd.4;. In this particular configuration, &man.ccd.4; was chosen. Setting Up the CCD The driver &man.ccd.4; allows you to take several identical disks and concatenate them into one logical file system. In order to use &man.ccd.4;, you need a kernel with &man.ccd.4; support built in. Add this line to your kernel configuration file, rebuild, and reinstall the kernel: pseudo-device ccd 4 On 5.X systems, you have to use instead the following line: device ccd In FreeBSD 5.X, it is not necessary to specify a number of &man.ccd.4; devices, as the &man.ccd.4; device driver is now self-cloning — new device instances will automatically be created on demand. The &man.ccd.4; support can also be loaded as a kernel loadable module in FreeBSD 3.0 or later. To set up &man.ccd.4;, you must first use &man.disklabel.8; to label the disks: disklabel -r -w ad1 auto disklabel -r -w ad2 auto disklabel -r -w ad3 auto This creates a disklabel for ad1c, ad2c and ad3c that spans the entire disk. Since &os; 5.1-RELEASE, the &man.bsdlabel.8; utility replaces the old &man.disklabel.8; program. With &man.bsdlabel.8; a number of obsolete options and parameters have been retired; in the examples above the option should be removed. For more information, please refer to the &man.bsdlabel.8; manual page. The next step is to change the disk label type. You can use &man.disklabel.8; to edit the disks: disklabel -e ad1 disklabel -e ad2 disklabel -e ad3 This opens up the current disk label on each disk with the editor specified by the EDITOR environment variable, typically &man.vi.1;. An unmodified disk label will look something like this: 8 partitions: # size offset fstype [fsize bsize bps/cpg] c: 60074784 0 unused 0 0 0 # (Cyl. 0 - 59597) Add a new e partition for &man.ccd.4; to use. This can usually be copied from the c partition, but the must be 4.2BSD. The disk label should now look something like this: 8 partitions: # size offset fstype [fsize bsize bps/cpg] c: 60074784 0 unused 0 0 0 # (Cyl. 0 - 59597) e: 60074784 0 4.2BSD 0 0 0 # (Cyl. 0 - 59597) Building the File System The device node for ccd0c may not exist yet, so to create it, perform the following commands: cd /dev sh MAKEDEV ccd0 In FreeBSD 5.0, &man.devfs.5; will automatically manage device nodes in /dev, so use of MAKEDEV is not necessary. Now that you have all of the disks labeled, you must build the &man.ccd.4;. To do that, use &man.ccdconfig.8;, with options similar to the following: ccdconfig ccd0 32 0 /dev/ad1e /dev/ad2e /dev/ad3e The use and meaning of each option is shown below: The first argument is the device to configure, in this case, /dev/ccd0c. The /dev/ portion is optional. The interleave for the file system. The interleave defines the size of a stripe in disk blocks, each normally 512 bytes. So, an interleave of 32 would be 16,384 bytes. Flags for &man.ccdconfig.8;. If you want to enable drive mirroring, you can specify a flag here. This configuration does not provide mirroring for &man.ccd.4;, so it is set at 0 (zero). The final arguments to &man.ccdconfig.8; are the devices to place into the array. Use the complete pathname for each device. After running &man.ccdconfig.8; the &man.ccd.4; is configured. A file system can be installed. Refer to &man.newfs.8; for options, or simply run: newfs /dev/ccd0c Making it All Automatic Generally, you will want to mount the &man.ccd.4; upon each reboot. To do this, you must configure it first. Write out your current configuration to /etc/ccd.conf using the following command: ccdconfig -g > /etc/ccd.conf During reboot, the script /etc/rc runs ccdconfig -C if /etc/ccd.conf exists. This automatically configures the &man.ccd.4; so it can be mounted. If you are booting into single user mode, before you can &man.mount.8; the &man.ccd.4;, you need to issue the following command to configure the array: ccdconfig -C To automatically mount the &man.ccd.4;, place an entry for the &man.ccd.4; in /etc/fstab so it will be mounted at boot time: /dev/ccd0c /media ufs rw 2 2 The Vinum Volume Manager RAIDsoftware RAID Vinum The Vinum Volume Manager is a block device driver which implements virtual disk drives. It isolates disk hardware from the block device interface and maps data in ways which result in an increase in flexibility, performance and reliability compared to the traditional slice view of disk storage. &man.vinum.8; implements the RAID-0, RAID-1 and RAID-5 models, both individually and in combination. See for more information about &man.vinum.8;. Hardware RAID RAID hardware FreeBSD also supports a variety of hardware RAID controllers. These devices control a RAID subsystem without the need for FreeBSD specific software to manage the array. Using an on-card BIOS, the card controls most of the disk operations itself. The following is a brief setup description using a Promise IDE RAID controller. When this card is installed and the system is started up, it displays a prompt requesting information. Follow the instructions to enter the card's setup screen. From here, you have the ability to combine all the attached drives. After doing so, the disk(s) will look like a single drive to FreeBSD. Other RAID levels can be set up accordingly. Rebuilding ATA RAID1 Arrays FreeBSD allows you to hot-replace a failed disk in an array. This requires that you catch it before you reboot. You will probably see something like the following in /var/log/messages or in the &man.dmesg.8; output: ad6 on monster1 suffered a hard error. ad6: READ command timeout tag=0 serv=0 - resetting ad6: trying fallback to PIO mode ata3: resetting devices .. done ad6: hard error reading fsbn 1116119 of 0-7 (ad6 bn 1116119; cn 1107 tn 4 sn 11) status=59 error=40 ar0: WARNING - mirror lost Using &man.atacontrol.8;, check for further information: &prompt.root; atacontrol list ATA channel 0: Master: no device present Slave: acd0 <HL-DT-ST CD-ROM GCR-8520B/1.00> ATA/ATAPI rev 0 ATA channel 1: Master: no device present Slave: no device present ATA channel 2: Master: ad4 <MAXTOR 6L080J4/A93.0500> ATA/ATAPI rev 5 Slave: no device present ATA channel 3: Master: ad6 <MAXTOR 6L080J4/A93.0500> ATA/ATAPI rev 5 Slave: no device present &prompt.root; atacontrol status ar0 ar0: ATA RAID1 subdisks: ad4 ad6 status: DEGRADED You will first need to detach the disk from the array so that you can safely remove it: &prompt.root; atacontrol detach 3 Replace the disk. Reattach the disk as a spare: &prompt.root; atacontrol attach 3 Master: ad6 <MAXTOR 6L080J4/A93.0500> ATA/ATAPI rev 5 Slave: no device present Rebuild the array: &prompt.root; atacontrol rebuild ar0 The rebuild command hangs until complete. However, it is possible to open another terminal (using Alt Fn) and check on the progress by issuing the following command: &prompt.root; dmesg | tail -10 [output removed] ad6: removed from configuration ad6: deleted from ar0 disk1 ad6: inserted into ar0 disk1 as spare &prompt.root; atacontrol status ar0 ar0: ATA RAID1 subdisks: ad4 ad6 status: REBUILDING 0% completed Wait until this operation completes. Mike Meyer Contributed by Creating and Using Optical Media (CDs) CDROMs creating Introduction CDs have a number of features that differentiate them from conventional disks. Initially, they were not writable by the user. They are designed so that they can be read continuously without delays to move the head between tracks. They are also much easier to transport between systems than similarly sized media were at the time. CDs do have tracks, but this refers to a section of data to be read continuously and not a physical property of the disk. To produce a CD on FreeBSD, you prepare the data files that are going to make up the tracks on the CD, then write the tracks to the CD. ISO 9660 file systems ISO 9660 The ISO 9660 file system was designed to deal with these differences. It unfortunately codifies file system limits that were common then. Fortunately, it provides an extension mechanism that allows properly written CDs to exceed those limits while still working with systems that do not support those extensions. sysutils/mkisofs The sysutils/mkisofs program is used to produce a data file containing an ISO 9660 file system. It has options that support various extensions, and is described below. You can install it with the sysutils/mkisofs port. CD burner ATAPI Which tool to use to burn the CD depends on whether your CD burner is ATAPI or something else. ATAPI CD burners use the burncd program that is part of the base system. SCSI and USB CD burners should use cdrecord from the sysutils/cdrtools port. burncd has a limited number of supported drives. To find out if a drive is supported, see the CD-R/RW supported drives list. CD burner ATAPI/CAM driver If you run &os; 5.X, &os; 4.8-RELEASE version or higher, it will be possible to use cdrecord and other tools for SCSI drives on an ATAPI hardware with the ATAPI/CAM module. mkisofs sysutils/mkisofs produces an ISO 9660 file system that is an image of a directory tree in the &unix; file system name space. The simplest usage is: &prompt.root; mkisofs -o imagefile.iso /path/to/tree file systems ISO 9660 This command will create an imagefile.iso containing an ISO 9660 file system that is a copy of the tree at /path/to/tree. In the process, it will map the file names to names that fit the limitations of the standard ISO 9660 file system, and will exclude files that have names uncharacteristic of ISO file systems. file systems HFS file systems Joliet A number of options are available to overcome those restrictions. In particular, enables the Rock Ridge extensions common to &unix; systems, enables Joliet extensions used by Microsoft systems, and can be used to create HFS file systems used by &macos;. For CDs that are going to be used only on FreeBSD systems, can be used to disable all filename restrictions. When used with , it produces a file system image that is identical to the FreeBSD tree you started from, though it may violate the ISO 9660 standard in a number of ways. CDROMs creating bootable The last option of general use is . This is used to specify the location of the boot image for use in producing an El Torito bootable CD. This option takes an argument which is the path to a boot image from the top of the tree being written to the CD. So, given that /tmp/myboot holds a bootable FreeBSD system with the boot image in /tmp/myboot/boot/cdboot, you could produce the image of an ISO 9660 file system in /tmp/bootable.iso like so: &prompt.root; mkisofs -U -R -b boot/cdboot -o /tmp/bootable.iso /tmp/myboot Having done that, if you have vn (FreeBSD 4.X), or md (FreeBSD 5.X) configured in your kernel, you can mount the file system with: &prompt.root; vnconfig -e vn0c /tmp/bootable.iso &prompt.root; mount -t cd9660 /dev/vn0c /mnt for FreeBSD 4.X, and for FreeBSD 5.X: &prompt.root; mdconfig -a -t vnode -f /tmp/bootable.iso -u 0 &prompt.root; mount -t cd9660 /dev/md0 /mnt At which point you can verify that /mnt and /tmp/myboot are identical. There are many other options you can use with sysutils/mkisofs to fine-tune its behavior. In particular: modifications to an ISO 9660 layout and the creation of Joliet and HFS discs. See the &man.mkisofs.8; manual page for details. burncd CDROMs burning If you have an ATAPI CD burner, you can use the burncd command to burn an ISO image onto a CD. burncd is part of the base system, installed as /usr/sbin/burncd. Usage is very simple, as it has few options: &prompt.root; burncd -f cddevice data imagefile.iso fixate Will burn a copy of imagefile.iso on cddevice. The default device is /dev/acd0c. See &man.burncd.8; for options to set the write speed, eject the CD after burning, and write audio data. cdrecord If you do not have an ATAPI CD burner, you will have to use cdrecord to burn your CDs. cdrecord is not part of the base system; you must install it from either the port at sysutils/cdrtools or the appropriate package. Changes to the base system can cause binary versions of this program to fail, possibly resulting in a coaster. You should therefore either upgrade the port when you upgrade your system, or if you are tracking -STABLE, upgrade the port when a new version becomes available. While cdrecord has many options, basic usage is even simpler than burncd. Burning an ISO 9660 image is done with: &prompt.root; cdrecord dev=device imagefile.iso The tricky part of using cdrecord is finding the to use. To find the proper setting, use the flag of cdrecord, which might produce results like this: CDROMs burning &prompt.root; cdrecord -scanbus Cdrecord 1.9 (i386-unknown-freebsd4.2) Copyright (C) 1995-2000 Jörg Schilling Using libscg version 'schily-0.1' scsibus0: 0,0,0 0) 'SEAGATE ' 'ST39236LW ' '0004' Disk 0,1,0 1) 'SEAGATE ' 'ST39173W ' '5958' Disk 0,2,0 2) * 0,3,0 3) 'iomega ' 'jaz 1GB ' 'J.86' Removable Disk 0,4,0 4) 'NEC ' 'CD-ROM DRIVE:466' '1.26' Removable CD-ROM 0,5,0 5) * 0,6,0 6) * 0,7,0 7) * scsibus1: 1,0,0 100) * 1,1,0 101) * 1,2,0 102) * 1,3,0 103) * 1,4,0 104) * 1,5,0 105) 'YAMAHA ' 'CRW4260 ' '1.0q' Removable CD-ROM 1,6,0 106) 'ARTEC ' 'AM12S ' '1.06' Scanner 1,7,0 107) * This lists the appropriate value for the devices on the list. Locate your CD burner, and use the three numbers separated by commas as the value for . In this case, the CRW device is 1,5,0, so the appropriate input would be . There are easier ways to specify this value; see &man.cdrecord.1; for details. That is also the place to look for information on writing audio tracks, controlling the speed, and other things. Duplicating Audio CDs You can duplicate an audio CD by extracting the audio data from the CD to a series of files, and then writing these files to a blank CD. The process is slightly different for ATAPI and SCSI drives. SCSI Drives Use cdda2wav to extract the audio. &prompt.user; cdda2wav -v255 -D2,0 -B -Owav Use cdrecord to write the .wav files. &prompt.user; cdrecord -v dev=2,0 -dao -useinfo *.wav Make sure that 2.0 is set appropriately, as described in . ATAPI Drives The ATAPI CD driver makes each track available as /dev/acddtnn, where d is the drive number, and nn is the track number written with two decimal digits, prefixed with zero as needed. So the first track on the first disk is /dev/acd0t01, the second is /dev/acd0t02, the third is /dev/acd0t03, and so on. Make sure the appropriate files exist in /dev. &prompt.root; cd /dev &prompt.root; sh MAKEDEV acd0t99 In FreeBSD 5.0, &man.devfs.5; will automatically create and manage entries in /dev for you, so it is not necessary to use MAKEDEV. Extract each track using &man.dd.1;. You must also use a specific block size when extracting the files. &prompt.root; dd if=/dev/acd0t01 of=track1.cdr bs=2352 &prompt.root; dd if=/dev/acd0t02 of=track2.cdr bs=2352 ... Burn the extracted files to disk using burncd. You must specify that these are audio files, and that burncd should fixate the disk when finished. &prompt.root; burncd -f /dev/acd0c audio track1.cdr track2.cdr ... fixate Duplicating Data CDs You can copy a data CD to a image file that is functionally equivalent to the image file created with sysutils/mkisofs, and you can use it to duplicate any data CD. The example given here assumes that your CDROM device is acd0. Substitute your correct CDROM device. A c must be appended to the end of the device name to indicate the entire partition or, in the case of CDROMs, the entire disc. &prompt.root; dd if=/dev/acd0c of=file.iso bs=2048 Now that you have an image, you can burn it to CD as described above. Using Data CDs Now that you have created a standard data CDROM, you probably want to mount it and read the data on it. By default, &man.mount.8; assumes that a file system is of type ufs. If you try something like: &prompt.root; mount /dev/cd0c /mnt you will get a complaint about Incorrect super block, and no mount. The CDROM is not a UFS file system, so attempts to mount it as such will fail. You just need to tell &man.mount.8; that the file system is of type ISO9660, and everything will work. You do this by specifying the option &man.mount.8;. For example, if you want to mount the CDROM device, /dev/cd0c, under /mnt, you would execute: &prompt.root; mount -t cd9660 /dev/cd0c /mnt Note that your device name (/dev/cd0c in this example) could be different, depending on the interface your CDROM uses. Also, the option just executes &man.mount.cd9660.8;. The above example could be shortened to: &prompt.root; mount_cd9660 /dev/cd0c /mnt You can generally use data CDROMs from any vendor in this way. Disks with certain ISO 9660 extensions might behave oddly, however. For example, Joliet disks store all filenames in two-byte Unicode characters. The FreeBSD kernel does not speak Unicode (yet!), so non-English characters show up as question marks. (If you are running FreeBSD 4.3 or later, the CD9660 driver includes hooks to load an appropriate Unicode conversion table on the fly. Modules for some of the common encodings are available via the sysutils/cd9660_unicode port.) Occasionally, you might get Device not configured when trying to mount a CDROM. This usually means that the CDROM drive thinks that there is no disk in the tray, or that the drive is not visible on the bus. It can take a couple of seconds for a CDROM drive to realize that it has been fed, so be patient. Sometimes, a SCSI CDROM may be missed because it didn't have enough time to answer the bus reset. If you have a SCSI CDROM please add the following option to your kernel configuration and rebuild your kernel. options SCSI_DELAY=15000 This tells your SCSI bus to pause 15 seconds during boot, to give your CDROM drive every possible chance to answer the bus reset. Burning Raw Data CDs You can choose to burn a file directly to CD, without creating an ISO 9660 file system. Some people do this for backup purposes. This runs more quickly than burning a standard CD: &prompt.root; burncd -f /dev/acd1c -s 12 data archive.tar.gz fixate In order to retrieve the data burned to such a CD, you must read data from the raw device node: &prompt.root; tar xzvf /dev/acd1c You cannot mount this disk as you would a normal CDROM. Such a CDROM cannot be read under any operating system except FreeBSD. If you want to be able to mount the CD, or share data with another operating system, you must use sysutils/mkisofs as described above. CD burner ATAPI/CAM driver Using the ATAPI/CAM Driver This driver allows ATAPI devices (CD-ROM, CD-RW, DVD drives etc...) to be accessed through the SCSI subsystem, and so allows the use of applications like sysutils/cdrdao or &man.cdrecord.1;. To use this driver, you will need to add the following lines to your kernel configuration file: device atapicam device scbus device cd device pass You also need the following lines in your kernel configuration file: device ata device atapicd Both of which should already be present. Then rebuild, install your new kernel, and reboot your machine. During the boot process, your burner should show up, like so: acd0: CD-RW <MATSHITA CD-RW/DVD-ROM UJDA740> at ata1-master PIO4 cd0 at ata1 bus 0 target 0 lun 0 cd0: <MATSHITA CDRW/DVD UJDA740 1.00> Removable CD-ROM SCSI-0 device cd0: 16.000MB/s transfers cd0: Attempt to query device size failed: NOT READY, Medium not present - tray closed The drive could now be accessed via the /dev/cd0 device name, for example to mount a CD-ROM on /mnt, just type the following: &prompt.root; mount -t cd9660 /dev/cd0c /mnt As root, you can run the following command to get the SCSI address of the burner: &prompt.root; camcontrol devlist <MATSHITA CDRW/DVD UJDA740 1.00> at scbus1 target 0 lun 0 (pass0,cd0) So 1,0,0 will be the SCSI address to use with &man.cdrecord.1; and other SCSI application. For more information about ATAPI/CAM and SCSI system, refer to the &man.atapicam.4; and &man.cam.4; manual pages. Marc Fonvieille Contributed by Creating and Using Optical Media (DVDs) DVD burning Introduction Compared to the CD, the DVD is the next generation of optical media storage technology. The DVD can hold more data than any CD and is nowadays the standard for video publishing. Five physical recordable formats can be defined for what we will call a recordable DVD: DVD-R: This was the first DVD recordable format available. The DVD-R standard is defined by the DVD Forum. This format is write once. DVD-RW: This is the rewriteable version of the DVD-R standard. A DVD-RW can be rewritten about 1000 times. DVD-RAM: This is also a rewriteable format supported by the DVD Forum. A DVD-RAM can be seen as a removable hard drive. However, this media is not compatible with most DVD-ROM drives and DVD-Video players; only few DVD writers will support the DVD-RAM. DVD+RW: This is a rewriteable format defined by the DVD+RW Alliance. A DVD+RW can be rewritten about 1000 times. DVD+R: This format is the write once variation of the DVD+RW format. A single layer recordable DVD can hold up to 4,700,000,000 bytes which is actually 4.38 GB or 4485 MB (1 kilobyte is 1024 bytes). A difference must be done between the physical media and the application. For example a DVD-Video is a specific file system that can be written on any recordable DVD physical media: DVD-R, DVD+R, DVD-RW etc. Before choosing the type of media, you just must be sure the burner and the DVD-Video player (a standalone player or a DVD-ROM drive on a computer) are compatible with the media. Configuration The program &man.growisofs.1; will be used to perform DVD recording. This command is part of the dvd+rw-tools utilities (sysutils/dvd+rw-tools). The dvd+rw-tools support all DVD media types. These tools use the SCSI subsystem to access to the devices, therefore the ATAPI/CAM support must be added to your kernel. Before attempting to use the dvd+rw-tools you should consult the dvd+rw-tools' hardware compatibility notes for any information related to your DVD burner. Burning Data DVDs The &man.growisofs.1; command is a frontend to mkisofs, it will invoke &man.mkisofs.8; to create the file system layout and will perform the write on the DVD. This means you do not need to create an image of the data before the burning process. To burn onto a DVD+R or a DVD-R the data from the /path/to/data directory, use the following command: &prompt.root; growisofs -dvd-compat -Z /dev/cd0 -J -R /path/to/data The options are passed to &man.mkisofs.8; for the file system creation (in this case: an ISO 9660 file system with Joliet and Rock Ridge extensions), consult the &man.mkisofs.8; manual page for more details. The option is used for the initial session recording in any case: multiple sessions or not. The DVD device, /dev/cd0, must be changed according to your configuration. The parameter will close the disk, the recording will be unappendable. This should provide more media compatibility with DVD-ROM drives. It is also possible to burn a pre-mastered image, for example to burn the image imagefile.iso, we will run: &prompt.root; growisofs -dvd-compat -Z /dev/cd0=imagefile.iso The write speed should be detected and automatically set according to the media and the drive being used. If you want to force the write speed, use the parameter. For more information, read the &man.growisofs.1; manual page. DVD DVD-Video Burning a DVD-Video A DVD-Video is a specific file system based on ISO 9660 and the micro-UDF (M-UDF) specifications. The DVD-Video also presents a specific file structure hierarchy, it is the reason why you need a particular program such as sysutils/dvdauthor to author the DVD. If you already have an image of the DVD-Video file system, just burn it in the same way as for any image, see the previous section for an example. If you have made the DVD authoring and the result is in, for example, the directory /path/to/video, the following command should be used to burn the DVD-Video: &prompt.root; growisofs -Z /dev/cd0 -dvd-video /path/to/video The option will tell &man.mkisofs.8; to create a DVD-Video file system layout. DVD DVD+RW Using a DVD+RW Unlike CD-RW, a virgin DVD+RW needs to be formatted before first use. To format the DVD+RW, use the following: &prompt.root; dvd+rw-format /dev/cd0 You need to perform this operation just once, keep in mind that only virgin DVD+RW medias need to be formatted. Then you can burn the DVD+RW in the way seen in previous sections. If you want to burn new data (burn a totally new file system not append some data) onto a DVD+RW, you do not need to blank it, you just have to write over the previous recording (in performing a new initial session), like this: &prompt.root; growisofs -Z /dev/cd0 -J -R /path/to/newdata DVD+RW format offers the possibility to easily append data to a previous recording. The operation consists in merging a new session to the existing one, it is not multisession writing, &man.growisofs.1; will grow the ISO 9660 file system present on the media. For example, if we want to append data to our previous DVD+RW, we have to use the following: &prompt.root; growisofs -M /dev/cd0 -J -R /path/to/nextdata The same &man.mkisofs.8; options we used to burn the initial session should be used during next writes. You must not use the option during the initial session if you want to be able to append any data, or you will have to rewrite a new initial session. If for any reason you really want to blank the media, do the following: &prompt.root; growisofs -Z /dev/cd0=/dev/zero DVD DVD-RW Using a DVD-RW A DVD-RW accepts two disc formats: the incremental sequential one and the restricted overwrite. By default DVD-RW discs are in sequential format. A virgin DVD-RW can be directly written without the need of a formatting operation, however a non-virgin DVD-RW in sequential format needs to be blanked before to be able to write a new initial session. To blank a DVD-RW in sequential mode, run: &prompt.root; dvd+rw-format -blank=full /dev/cd0 A full blanking () will take about one hour on a 1x media. A fast blanking can be performed using the option if the DVD-RW will be recorded in Disk-At-Once (DAO) mode. To burn the DVD-RW in DAO mode, use the command: &prompt.root; growisofs -use-the-force-luke=dao -Z /dev/cd0=imagefile.iso The option should not be required since &man.growisofs.1; attempts to detect minimally (fast blanked) media and engage DAO write. In fact one should use restricted overwrite mode with any DVD-RW, this format is more flexible than the default incremental sequential one. To write data on a sequential DVD-RW, use the same instructions as for the other DVD formats: &prompt.root; growisofs -Z /dev/cd0 -J -R /path/to/data If you want to append some data to your previous recording, you will have to use the &man.growisofs.1; option. However, if you perform data addition on a DVD-RW in incremental sequential mode, a new session will be created on the disc and the result will be a multi-session disc. A DVD-RW in restricted overwrite format does not need to be blanked before a new initial session, you just have to overwrite the disc with the option, this is similar to the DVD+RW case. It is also possible to grow an existing ISO 9660 file system written on the disc in a same way as for a DVD+RW with the option. The result will be a one-session DVD. To put a DVD-RW in the restricted overwrite format, the following command must be used: &prompt.root; dvd+rw-format /dev/cd0 To change back to the sequential format use: &prompt.root; dvd+rw-format -blank=full /dev/cd0 Multisession Very few DVD-ROM and DVD-Video players support multisession DVDs, they will most of time, hopefully, only read the first session. DVD+R, DVD-R and DVD-RW in sequential format can accept multiple sessions, the notion of multiple sessions does not exist for the DVD+RW and the DVD-RW restricted overwrite formats. Using the following command after an initial (non-closed) session on a DVD+R, DVD-R, or DVD-RW in sequential format, will add a new session to the disc: &prompt.root; growisofs -M /dev/cd0 -J -R /path/to/nextdata For More Information To obtain more information about a DVD, the dvd+rw-mediainfo /dev/cd0 command can be ran with the disc in the drive. More information about the dvd+rw-tools can be found in the &man.growisofs.1; manual page, on the dvd+rw-tools web site and in the cdwrite mailing list archives. Julio Merino Original work by Martin Karlsson Rewritten by Creating and Using Floppy Disks Storing data on floppy disks is sometimes useful, for example when one does not have any other removable storage media or when one needs to transfer small amounts of data to another computer. This section will explain how to use floppy disks in FreeBSD. It will primarily cover formatting and usage of 3.5inch DOS floppies, but the concepts are similar for other floppy disk formats. Formatting Floppies The Device Floppy disks are accessed through entries in /dev, just like other devices. To access the raw floppy disk in 4.X and earlier releases, one uses /dev/fdN, where N stands for the drive number, usually 0, or /dev/fdNX, where X stands for a letter. In 5.0 or newer releases, simply use /dev/fdN. The Disk Size in 4.X and Earlier Releases There are also /dev/fdN.size devices, where size is a floppy disk size in kilobytes. These entries are used at low-level format time to determine the disk size. 1440kB is the size that will be used in the following examples. Sometimes the entries under /dev will have to be (re)created. To do that, issue: &prompt.root; cd /dev && ./MAKEDEV "fd*" The Disk Size in 5.0 and Newer Releases In 5.0, &man.devfs.5; will automatically manage device nodes in /dev, so use of MAKEDEV is not necessary. The desired disk size is passed to &man.fdformat.1; through the flag. Supported sizes are listed in &man.fdcontrol.8;, but be advised that 1440kB is what works best. Formatting A floppy disk needs to be low-level formated before it can be used. This is usually done by the vendor, but formatting is a good way to check media integrity. Although it is possible to force larger (or smaller) disk sizes, 1440kB is what most floppy disks are designed for. To low-level format the floppy disk you need to use &man.fdformat.1;. This utility expects the device name as an argument. Make note of any error messages, as these can help determine if the disk is good or bad. Formatting in 4.X and Earlier Releases Use the /dev/fdN.size devices to format the floppy. Insert a new 3.5inch floppy disk in your drive and issue: &prompt.root; /usr/sbin/fdformat /dev/fd0.1440 Formatting in 5.0 and Newer Releases Use the /dev/fdN devices to format the floppy. Insert a new 3.5inch floppy disk in your drive and issue: &prompt.root; /usr/sbin/fdformat -f 1440 /dev/fd0 The Disk Label After low-level formatting the disk, you will need to place a disk label on it. This disk label will be destroyed later, but it is needed by the system to determine the size of the disk and its geometry later. The new disk label will take over the whole disk, and will contain all the proper information about the geometry of the floppy. The geometry values for the disk label are listed in /etc/disktab. You can run now &man.disklabel.8; like so: &prompt.root; /sbin/disklabel -B -r -w /dev/fd0 fd1440 Since &os; 5.1-RELEASE, the &man.bsdlabel.8; utility replaces the old &man.disklabel.8; program. With &man.bsdlabel.8; a number of obsolete options and parameters have been retired; in the example above the option should be removed. For more information, please refer to the &man.bsdlabel.8; manual page. The File System Now the floppy is ready to be high-level formated. This will place a new file system on it, which will let FreeBSD read and write to the disk. After creating the new file system, the disk label is destroyed, so if you want to reformat the disk, you will have to recreate the disk label. The floppy's file system can be either UFS or FAT. FAT is generally a better choice for floppies. To put a new file system on the floppy, issue: &prompt.root; /sbin/newfs_msdos /dev/fd0 The disk is now ready for use. Using the Floppy To use the floppy, mount it with &man.mount.msdos.8; (in 4.X and earlier releases) or &man.mount.msdosfs.8; (in 5.0 or newer releases). One can also use emulators/mtools from the ports collection. Creating and Using Data Tapes tape media The major tape media are the 4mm, 8mm, QIC, mini-cartridge and DLT. 4mm (DDS: Digital Data Storage) tape media DDS (4mm) tapes tape media QIC tapes 4mm tapes are replacing QIC as the workstation backup media of choice. This trend accelerated greatly when Conner purchased Archive, a leading manufacturer of QIC drives, and then stopped production of QIC drives. 4mm drives are small and quiet but do not have the reputation for reliability that is enjoyed by 8mm drives. The cartridges are less expensive and smaller (3 x 2 x 0.5 inches, 76 x 51 x 12 mm) than 8mm cartridges. 4mm, like 8mm, has comparatively short head life for the same reason, both use helical scan. Data throughput on these drives starts ~150 kB/s, peaking at ~500 kB/s. Data capacity starts at 1.3 GB and ends at 2.0 GB. Hardware compression, available with most of these drives, approximately doubles the capacity. Multi-drive tape library units can have 6 drives in a single cabinet with automatic tape changing. Library capacities reach 240 GB. The DDS-3 standard now supports tape capacities up to 12 GB (or 24 GB compressed). 4mm drives, like 8mm drives, use helical-scan. All the benefits and drawbacks of helical-scan apply to both 4mm and 8mm drives. Tapes should be retired from use after 2,000 passes or 100 full backups. 8mm (Exabyte) tape media Exabyte (8mm) tapes 8mm tapes are the most common SCSI tape drives; they are the best choice of exchanging tapes. Nearly every site has an Exabyte 2 GB 8mm tape drive. 8mm drives are reliable, convenient and quiet. Cartridges are inexpensive and small (4.8 x 3.3 x 0.6 inches; 122 x 84 x 15 mm). One downside of 8mm tape is relatively short head and tape life due to the high rate of relative motion of the tape across the heads. Data throughput ranges from ~250 kB/s to ~500 kB/s. Data sizes start at 300 MB and go up to 7 GB. Hardware compression, available with most of these drives, approximately doubles the capacity. These drives are available as single units or multi-drive tape libraries with 6 drives and 120 tapes in a single cabinet. Tapes are changed automatically by the unit. Library capacities reach 840+ GB. The Exabyte Mammoth model supports 12 GB on one tape (24 GB with compression) and costs approximately twice as much as conventional tape drives. Data is recorded onto the tape using helical-scan, the heads are positioned at an angle to the media (approximately 6 degrees). The tape wraps around 270 degrees of the spool that holds the heads. The spool spins while the tape slides over the spool. The result is a high density of data and closely packed tracks that angle across the tape from one edge to the other. QIC tape media QIC-150 QIC-150 tapes and drives are, perhaps, the most common tape drive and media around. QIC tape drives are the least expensive serious backup drives. The downside is the cost of media. QIC tapes are expensive compared to 8mm or 4mm tapes, up to 5 times the price per GB data storage. But, if your needs can be satisfied with a half-dozen tapes, QIC may be the correct choice. QIC is the most common tape drive. Every site has a QIC drive of some density or another. Therein lies the rub, QIC has a large number of densities on physically similar (sometimes identical) tapes. QIC drives are not quiet. These drives audibly seek before they begin to record data and are clearly audible whenever reading, writing or seeking. QIC tapes measure (6 x 4 x 0.7 inches; 15.2 x 10.2 x 1.7 mm). Mini-cartridges, which also use 1/4" wide tape are discussed separately. Tape libraries and changers are not available. Data throughput ranges from ~150 kB/s to ~500 kB/s. Data capacity ranges from 40 MB to 15 GB. Hardware compression is available on many of the newer QIC drives. QIC drives are less frequently installed; they are being supplanted by DAT drives. Data is recorded onto the tape in tracks. The tracks run along the long axis of the tape media from one end to the other. The number of tracks, and therefore the width of a track, varies with the tape's capacity. Most if not all newer drives provide backward-compatibility at least for reading (but often also for writing). QIC has a good reputation regarding the safety of the data (the mechanics are simpler and more robust than for helical scan drives). Tapes should be retired from use after 5,000 backups. XXX* Mini-Cartridge DLT tape media DLT DLT has the fastest data transfer rate of all the drive types listed here. The 1/2" (12.5mm) tape is contained in a single spool cartridge (4 x 4 x 1 inches; 100 x 100 x 25 mm). The cartridge has a swinging gate along one entire side of the cartridge. The drive mechanism opens this gate to extract the tape leader. The tape leader has an oval hole in it which the drive uses to hook the tape. The take-up spool is located inside the tape drive. All the other tape cartridges listed here (9 track tapes are the only exception) have both the supply and take-up spools located inside the tape cartridge itself. Data throughput is approximately 1.5 MB/s, three times the throughput of 4mm, 8mm, or QIC tape drives. Data capacities range from 10 GB to 20 GB for a single drive. Drives are available in both multi-tape changers and multi-tape, multi-drive tape libraries containing from 5 to 900 tapes over 1 to 20 drives, providing from 50 GB to 9 TB of storage. With compression, DLT Type IV format supports up to 70 GB capacity. Data is recorded onto the tape in tracks parallel to the direction of travel (just like QIC tapes). Two tracks are written at once. Read/write head lifetimes are relatively long; once the tape stops moving, there is no relative motion between the heads and the tape. AIT tape media AIT AIT is a new format from Sony, and can hold up to 50 GB (with compression) per tape. The tapes contain memory chips which retain an index of the tape's contents. This index can be rapidly read by the tape drive to determine the position of files on the tape, instead of the several minutes that would be required for other tapes. Software such as SAMS:Alexandria can operate forty or more AIT tape libraries, communicating directly with the tape's memory chip to display the contents on screen, determine what files were backed up to which tape, locate the correct tape, load it, and restore the data from the tape. Libraries like this cost in the region of $20,000, pricing them a little out of the hobbyist market. Using a New Tape for the First Time The first time that you try to read or write a new, completely blank tape, the operation will fail. The console messages should be similar to: sa0(ncr1:4:0): NOT READY asc:4,1 sa0(ncr1:4:0): Logical unit is in process of becoming ready The tape does not contain an Identifier Block (block number 0). All QIC tape drives since the adoption of QIC-525 standard write an Identifier Block to the tape. There are two solutions: mt fsf 1 causes the tape drive to write an Identifier Block to the tape. Use the front panel button to eject the tape. Re-insert the tape and dump data to the tape. dump will report DUMP: End of tape detected and the console will show: HARDWARE FAILURE info:280 asc:80,96. rewind the tape using: mt rewind. Subsequent tape operations are successful. Backups to Floppies Can I Use Floppies for Backing Up My Data? backup floppies floppy disks Floppy disks are not really a suitable media for making backups as: The media is unreliable, especially over long periods of time. Backing up and restoring is very slow. They have a very limited capacity (the days of backing up an entire hard disk onto a dozen or so floppies has long since passed). However, if you have no other method of backing up your data then floppy disks are better than no backup at all. If you do have to use floppy disks then ensure that you use good quality ones. Floppies that have been lying around the office for a couple of years are a bad choice. Ideally use new ones from a reputable manufacturer. So How Do I Backup My Data to Floppies? The best way to backup to floppy disk is to use &man.tar.1; with the (multi volume) option, which allows backups to span multiple floppies. To backup all the files in the current directory and sub-directory use this (as root): &prompt.root; tar Mcvf /dev/fd0 * When the first floppy is full &man.tar.1; will prompt you to insert the next volume (because &man.tar.1; is media independent it refers to volumes; in this context it means floppy disk). Prepare volume #2 for /dev/fd0 and hit return: This is repeated (with the volume number incrementing) until all the specified files have been archived. Can I Compress My Backups? tar gzip compression Unfortunately, &man.tar.1; will not allow the option to be used for multi-volume archives. You could, of course, &man.gzip.1; all the files, &man.tar.1; them to the floppies, then &man.gunzip.1; the files again! How Do I Restore My Backups? To restore the entire archive use: &prompt.root; tar Mxvf /dev/fd0 There are two ways that you can use to restore only specific files. First, you can start with the first floppy and use: &prompt.root; tar Mxvf /dev/fd0 filename The utility &man.tar.1; will prompt you to insert subsequent floppies until it finds the required file. Alternatively, if you know which floppy the file is on then you can simply insert that floppy and use the same command as above. Note that if the first file on the floppy is a continuation from the previous one then &man.tar.1; will warn you that it cannot restore it, even if you have not asked it to! Backup Basics The three major backup programs are &man.dump.8;, &man.tar.1;, and &man.cpio.1;. Dump and Restore backup software dump / restore dump restore The traditional &unix; backup programs are dump and restore. They operate on the drive as a collection of disk blocks, below the abstractions of files, links and directories that are created by the file systems. dump backs up an entire file system on a device. It is unable to backup only part of a file system or a directory tree that spans more than one file system. dump does not write files and directories to tape, but rather writes the raw data blocks that comprise files and directories. If you use dump on your root directory, you would not back up /home, /usr or many other directories since these are typically mount points for other file systems or symbolic links into those file systems. dump has quirks that remain from its early days in Version 6 of AT&T UNIX (circa 1975). The default parameters are suitable for 9-track tapes (6250 bpi), not the high-density media available today (up to 62,182 ftpi). These defaults must be overridden on the command line to utilize the capacity of current tape drives. .rhosts It is also possible to backup data across the network to a tape drive attached to another computer with rdump and rrestore. Both programs rely upon rcmd and ruserok to access the remote tape drive. Therefore, the user performing the backup must be listed in the .rhosts file on the remote computer. The arguments to rdump and rrestore must be suitable to use on the remote computer. When rdumping from a FreeBSD computer to an Exabyte tape drive connected to a Sun called komodo, use: &prompt.root; /sbin/rdump 0dsbfu 54000 13000 126 komodo:/dev/nsa8 /dev/da0a 2>&1 Beware: there are security implications to allowing .rhosts authentication. Evaluate your situation carefully. It is also possible to use dump and restore in a more secure fashion over ssh. Using <command>dump</command> over <application>ssh</application> &prompt.root; /sbin/dump -0uan -f - /usr | gzip -2 | ssh1 -c blowfish \ targetuser@targetmachine.example.com dd of=/mybigfiles/dump-usr-l0.gz Or using dump's built-in method, setting the enviroment variable RSH: Using <command>dump</command> over <application>ssh</application> with <envar>RSH</envar> set &prompt.root; RSH=/usr/bin/ssh /sbin/dump -0uan -f targetuser@targetmachine.example.com:/dev/sa0 <command>tar</command> backup software tar &man.tar.1; also dates back to Version 6 of AT&T UNIX (circa 1975). tar operates in cooperation with the file system; tar writes files and directories to tape. tar does not support the full range of options that are available from &man.cpio.1;, but tar does not require the unusual command pipeline that cpio uses. tar Most versions of tar do not support backups across the network. The GNU version of tar, which FreeBSD utilizes, supports remote devices using the same syntax as rdump. To tar to an Exabyte tape drive connected to a Sun called komodo, use: &prompt.root; /usr/bin/tar cf komodo:/dev/nsa8 . 2>&1 For versions without remote device support, you can use a pipeline and rsh to send the data to a remote tape drive. &prompt.root; tar cf - . | rsh hostname dd of=tape-device obs=20b If you are worried about the security of backing up over a network you should use the ssh command instead of rsh. <command>cpio</command> backup software cpio &man.cpio.1; is the original &unix; file interchange tape program for magnetic media. cpio has options (among many others) to perform byte-swapping, write a number of different archive formats, and pipe the data to other programs. This last feature makes cpio an excellent choice for installation media. cpio does not know how to walk the directory tree and a list of files must be provided through stdin. cpio cpio does not support backups across the network. You can use a pipeline and rsh to send the data to a remote tape drive. &prompt.root; for f in directory_list; do find $f >> backup.list done &prompt.root; cpio -v -o --format=newc < backup.list | ssh user@host "cat > backup_device" Where directory_list is the list of directories you want to back up, user@host is the user/hostname combination that will be performing the backups, and backup_device is where the backups should be written to (e.g., /dev/nsa0). <command>pax</command> backup software pax pax POSIX IEEE &man.pax.1; is IEEE/&posix;'s answer to tar and cpio. Over the years the various versions of tar and cpio have gotten slightly incompatible. So rather than fight it out to fully standardize them, &posix; created a new archive utility. pax attempts to read and write many of the various cpio and tar formats, plus new formats of its own. Its command set more resembles cpio than tar. <application>Amanda</application> backup software Amanda Amanda Amanda (Advanced Maryland Network Disk Archiver) is a client/server backup system, rather than a single program. An Amanda server will backup to a single tape drive any number of computers that have Amanda clients and a network connection to the Amanda server. A common problem at sites with a number of large disks is that the length of time required to backup to data directly to tape exceeds the amount of time available for the task. Amanda solves this problem. Amanda can use a holding disk to backup several file systems at the same time. Amanda creates archive sets: a group of tapes used over a period of time to create full backups of all the file systems listed in Amanda's configuration file. The archive set also contains nightly incremental (or differential) backups of all the file systems. Restoring a damaged file system requires the most recent full backup and the incremental backups. The configuration file provides fine control of backups and the network traffic that Amanda generates. Amanda will use any of the above backup programs to write the data to tape. Amanda is available as either a port or a package, it is not installed by default. Do Nothing Do nothing is not a computer program, but it is the most widely used backup strategy. There are no initial costs. There is no backup schedule to follow. Just say no. If something happens to your data, grin and bear it! If your time and your data is worth little to nothing, then Do nothing is the most suitable backup program for your computer. But beware, &unix; is a useful tool, you may find that within six months you have a collection of files that are valuable to you. Do nothing is the correct backup method for /usr/obj and other directory trees that can be exactly recreated by your computer. An example is the files that comprise the HTML or &postscript; version of this Handbook. These document formats have been created from SGML input files. Creating backups of the HTML or &postscript; files is not necessary. The SGML files are backed up regularly. Which Backup Program Is Best? LISA &man.dump.8; Period. Elizabeth D. Zwicky torture tested all the backup programs discussed here. The clear choice for preserving all your data and all the peculiarities of &unix; file systems is dump. Elizabeth created file systems containing a large variety of unusual conditions (and some not so unusual ones) and tested each program by doing a backup and restore of those file systems. The peculiarities included: files with holes, files with holes and a block of nulls, files with funny characters in their names, unreadable and unwritable files, devices, files that change size during the backup, files that are created/deleted during the backup and more. She presented the results at LISA V in Oct. 1991. See torture-testing Backup and Archive Programs. Emergency Restore Procedure Before the Disaster There are only four steps that you need to perform in preparation for any disaster that may occur. disklabel First, print the disklabel from each of your disks (e.g. disklabel da0 | lpr), your file system table (/etc/fstab) and all boot messages, two copies of each. fix-it floppies Second, determine that the boot and fix-it floppies (boot.flp and fixit.flp) have all your devices. The easiest way to check is to reboot your machine with the boot floppy in the floppy drive and check the boot messages. If all your devices are listed and functional, skip on to step three. Otherwise, you have to create two custom bootable floppies which have a kernel that can mount all of your disks and access your tape drive. These floppies must contain: fdisk, disklabel, newfs, mount, and whichever backup program you use. These programs must be statically linked. If you use dump, the floppy must contain restore. Third, create backup tapes regularly. Any changes that you make after your last backup may be irretrievably lost. Write-protect the backup tapes. Fourth, test the floppies (either boot.flp and fixit.flp or the two custom bootable floppies you made in step two.) and backup tapes. Make notes of the procedure. Store these notes with the bootable floppy, the printouts and the backup tapes. You will be so distraught when restoring that the notes may prevent you from destroying your backup tapes (How? In place of tar xvf /dev/sa0, you might accidentally type tar cvf /dev/sa0 and over-write your backup tape). For an added measure of security, make bootable floppies and two backup tapes each time. Store one of each at a remote location. A remote location is NOT the basement of the same office building. A number of firms in the World Trade Center learned this lesson the hard way. A remote location should be physically separated from your computers and disk drives by a significant distance. A Script for Creating a Bootable Floppy /mnt/sbin/init gzip -c -best /sbin/fsck > /mnt/sbin/fsck gzip -c -best /sbin/mount > /mnt/sbin/mount gzip -c -best /sbin/halt > /mnt/sbin/halt gzip -c -best /sbin/restore > /mnt/sbin/restore gzip -c -best /bin/sh > /mnt/bin/sh gzip -c -best /bin/sync > /mnt/bin/sync cp /root/.profile /mnt/root cp -f /dev/MAKEDEV /mnt/dev chmod 755 /mnt/dev/MAKEDEV chmod 500 /mnt/sbin/init chmod 555 /mnt/sbin/fsck /mnt/sbin/mount /mnt/sbin/halt chmod 555 /mnt/bin/sh /mnt/bin/sync chmod 6555 /mnt/sbin/restore # # create the devices nodes # cd /mnt/dev ./MAKEDEV std ./MAKEDEV da0 ./MAKEDEV da1 ./MAKEDEV da2 ./MAKEDEV sa0 ./MAKEDEV pty0 cd / # # create minimum file system table # cat > /mnt/etc/fstab < /mnt/etc/passwd < /mnt/etc/master.passwd < After the Disaster The key question is: did your hardware survive? You have been doing regular backups so there is no need to worry about the software. If the hardware has been damaged, the parts should be replaced before attempting to use the computer. If your hardware is okay, check your floppies. If you are using a custom boot floppy, boot single-user (type -s at the boot: prompt). Skip the following paragraph. If you are using the boot.flp and fixit.flp floppies, keep reading. Insert the boot.flp floppy in the first floppy drive and boot the computer. The original install menu will be displayed on the screen. Select the Fixit--Repair mode with CDROM or floppy. option. Insert the fixit.flp when prompted. restore and the other programs that you need are located in /mnt2/stand. Recover each file system separately. mount root partition disklabel newfs Try to mount (e.g. mount /dev/da0a /mnt) the root partition of your first disk. If the disklabel was damaged, use disklabel to re-partition and label the disk to match the label that you printed and saved. Use newfs to re-create the file systems. Re-mount the root partition of the floppy read-write (mount -u -o rw /mnt). Use your backup program and backup tapes to recover the data for this file system (e.g. restore vrf /dev/sa0). Unmount the file system (e.g. umount /mnt). Repeat for each file system that was damaged. Once your system is running, backup your data onto new tapes. Whatever caused the crash or data loss may strike again. Another hour spent now may save you from further distress later. * I Did Not Prepare for the Disaster, What Now? ]]> Marc Fonvieille Reorganized and enhanced by Network, Memory, and File-Backed File Systems virtual disks disks virtual Aside from the disks you physically insert into your computer: floppies, CDs, hard drives, and so forth; other forms of disks are understood by FreeBSD - the virtual disks. NFS Coda disks memory These include network file systems such as the Network File System and Coda, memory-based file systems and file-backed file systems. According to the FreeBSD version you run, you will have to use different tools for creation and use of file-backed and memory-based file systems. The FreeBSD 4.X users will have to use &man.MAKEDEV.8; to create the required devices. FreeBSD 5.0 and later use &man.devfs.5; to allocate device nodes transparently for the user. File-Backed File System under FreeBSD 4.X disks file-backed (4.X) The utility &man.vnconfig.8; configures and enables vnode pseudo-disk devices. A vnode is a representation of a file, and is the focus of file activity. This means that &man.vnconfig.8; uses files to create and operate a file system. One possible use is the mounting of floppy or CD images kept in files. To use &man.vnconfig.8;, you need &man.vn.4; support in your kernel configuration file: pseudo-device vn To mount an existing file system image: Using vnconfig to Mount an Existing File System Image under FreeBSD 4.X &prompt.root; vnconfig vn0 diskimage &prompt.root; mount /dev/vn0c /mnt To create a new file system image with &man.vnconfig.8;: Creating a New File-Backed Disk with <command>vnconfig</command> &prompt.root; dd if=/dev/zero of=newimage bs=1k count=5k 5120+0 records in 5120+0 records out &prompt.root; vnconfig -s labels -c vn0 newimage &prompt.root; disklabel -r -w vn0 auto &prompt.root; newfs vn0c Warning: 2048 sector(s) in last cylinder unallocated /dev/vn0c: 10240 sectors in 3 cylinders of 1 tracks, 4096 sectors 5.0MB in 1 cyl groups (16 c/g, 32.00MB/g, 1280 i/g) super-block backups (for fsck -b #) at: 32 &prompt.root; mount /dev/vn0c /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/vn0c 4927 1 4532 0% /mnt File-Backed File System under FreeBSD 5.X disks file-backed (5.X) The utility &man.mdconfig.8; is used to configure and enable memory disks, &man.md.4;, under FreeBSD 5.X. To use &man.mdconfig.8;, you have to load &man.md.4; module or to add the support in your kernel configuration file: device md The &man.mdconfig.8; command supports three kinds of memory backed virtual disks: memory disks allocated with &man.malloc.9;, memory disks using a file or swap space as backing. One possible use is the mounting of floppy or CD images kept in files. To mount an existing file system image: Using <command>mdconfig</command> to Mount an Existing File System Image under FreeBSD 5.X &prompt.root; mdconfig -a -t vnode -f diskimage -u 0 &prompt.root; mount /dev/md0c /mnt To create a new file system image with &man.mdconfig.8;: Creating a New File-Backed Disk with <command>mdconfig</command> &prompt.root; dd if=/dev/zero of=newimage bs=1k count=5k 5120+0 records in 5120+0 records out &prompt.root; mdconfig -a -t vnode -f newimage -u 0 &prompt.root; disklabel -r -w md0 auto &prompt.root; newfs md0c /dev/md0c: 5.0MB (10240 sectors) block size 16384, fragment size 2048 using 4 cylinder groups of 1.27MB, 81 blks, 256 inodes. super-block backups (for fsck -b #) at: 32, 2624, 5216, 7808 &prompt.root; mount /dev/md0c /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/md0c 4846 2 4458 0% /mnt If you do not specify the unit number with the option, &man.mdconfig.8; will use the &man.md.4; automatic allocation to select an unused device. The name of the allocated unit will be output on stdout like md4. For more details about &man.mdconfig.8;, please refer to the manual page. Since &os; 5.1-RELEASE, the &man.bsdlabel.8; utility replaces the old &man.disklabel.8; program. With &man.bsdlabel.8; a number of obsolete options and parameters have been retired; in the example above the option should be removed. For more information, please refer to the &man.bsdlabel.8; manual page. The utility &man.mdconfig.8; is very useful, however it asks many command lines to create a file-backed file system. FreeBSD 5.0 also comes with a tool called &man.mdmfs.8;, this program configures a &man.md.4; disk using &man.mdconfig.8;, puts a UFS file system on it using &man.newfs.8;, and mounts it using &man.mount.8;. For example, if you want to create and mount the same file system image as above, simply type the following: Configure and Mount a File-Backed Disk with <command>mdmfs</command> &prompt.root; dd if=/dev/zero of=newimage bs=1k count=5k 5120+0 records in 5120+0 records out &prompt.root; mdmfs -F newimage -s 5m md0 /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/md0 4846 2 4458 0% /mnt If you use the option without unit number, &man.mdmfs.8; will use &man.md.4; auto-unit feature to automatically select an unused device. For more details about &man.mdmfs.8;, please refer to the manual page. Memory-Based File System under FreeBSD 4.X disks memory file system (4.X) The &man.md.4; driver is a simple, efficient means to create memory file systems under FreeBSD 4.X. &man.malloc.9; is used to allocate the memory. Simply take a file system you have prepared with, for example, &man.vnconfig.8;, and: md Memory Disk under FreeBSD 4.X &prompt.root; dd if=newimage of=/dev/md0 5120+0 records in 5120+0 records out &prompt.root; mount /dev/md0c /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/md0c 4927 1 4532 0% /mnt For more details, please refer to &man.md.4; manual page. Memory-Based File System under FreeBSD 5.X disks memory file system (5.X) The same tools are used for memory-based and file-backed file systems: &man.mdconfig.8; or &man.mdmfs.8;. The storage for memory-based file system is allocated with &man.malloc.9;. Creating a New Memory-Based Disk with <command>mdconfig</command> &prompt.root; mdconfig -a -t malloc -s 5m -u 1 &prompt.root; newfs -U md1 /dev/md1: 5.0MB (10240 sectors) block size 16384, fragment size 2048 using 4 cylinder groups of 1.27MB, 81 blks, 256 inodes. with soft updates super-block backups (for fsck -b #) at: 32, 2624, 5216, 7808 &prompt.root; mount /dev/md1 /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/md1 4846 2 4458 0% /mnt Creating a New Memory-Based Disk with <command>mdmfs</command> &prompt.root; mdmfs -M -s 5m md2 /mnt &prompt.root; df /mnt Filesystem 1K-blocks Used Avail Capacity Mounted on /dev/md2 4846 2 4458 0% /mnt Instead of using a &man.malloc.9; backed file system, it is possible to use swap, for that just replace with in the command line of &man.mdconfig.8;. The &man.mdmfs.8; utility by default (without ) creates a swap-based disk. For more details, please refer to &man.mdconfig.8; and &man.mdmfs.8; manual pages. Detaching a Memory Disk from the System disks detaching a memory disk When a memory-based or file-based file system is not used, you should release all resources to the system. The first thing to do is to unmount the file system, then use &man.mdconfig.8; to detach the disk from the system and release the resources. For example to detach and free all resources used by /dev/md4: &prompt.root; mdconfig -d -u 4 It is possible to list information about configured &man.md.4; devices in using the command mdconfig -l. For FreeBSD 4.X, &man.vnconfig.8; is used to detach the device. For example to detach and free all resources used by /dev/vn4: &prompt.root; vnconfig -u vn4 Tom Rhodes Contributed by File System Snapshots file systems snapshots FreeBSD 5.0 offers a new feature in conjunction with Soft Updates: File system snapshots. Snapshots allow a user to create images of specified file systems, and treat them as a file. Snapshot files must be created in the file system that the action is performed on, and a user may create no more than 20 snapshots per file system. Active snapshots are recorded in the superblock so they are persistent across unmount and remount operations along with system reboots. When a snapshot is no longer required, it can be removed with the standard &man.rm.1; command. Snapshots may be removed in any order, however all the used space may not be acquired because another snapshot will possibly claim some of the released blocks. During initial creation, the flag (see the &man.chflags.1; manual page) is set to ensure that even root cannot write to the snapshot. The &man.unlink.1; command makes an exception for snapshot files since it allows them to be removed with the flag set, so it is not necessary to clear the flag before removing a snapshot file. Snapshots are created with the &man.mount.8; command. To place a snapshot of /var in the file /var/snapshot/snap use the following command: &prompt.root; mount -u -o snapshot /var/snapshot/snap /var Alternatively, you can use &man.mksnap.ffs.8; to create a snapshot: &prompt.root; mksnap_ffs /var /var/snapshot/snap Once a snapshot has been created, it has several uses: Some administrators will use a snapshot file for backup purposes, because the snapshot can be transfered to CDs or tape. File integrity, &man.fsck.8; may be ran on the snapshot. Assuming that the file system was clean when it was mounted, you should always get a clean (and unchanging) result. This is essentially what the background &man.fsck.8; process does. Run the &man.dump.8; utility on the snapshot. A dump will be returned that is consistent with the file system and the timestamp of the snapshot. &man.dump.8; can also take a snapshot, create a dump image and then remove the snapshot in one command using the flag. &man.mount.8; the snapshot as a frozen image of the file system. To &man.mount.8; the snapshot /var/snapshot/snap run: -&prompt.root; mdconfig -a -t vnode -f /var/snapshot/snap -u 4 -&prompt.root; mount -r /dev/md4 /mnt +&prompt.root; mdconfig -a -t vnode -f /var/snapshot/snap -u 4 +&prompt.root; mount -r /dev/md4 /mnt You can now walk the hierarchy of your frozen /var file system mounted at /mnt. Everything will be in the same state it was during the snapshot creation time. The only exception is that any earlier snapshots will appear as zero length files. When the use of a snapshot has delimited, it can be unmounted with: -&prompt.root; umount /mnt -&prompt.root; mdconfig -d -u 4 +&prompt.root; umount /mnt +&prompt.root; mdconfig -d -u 4 For more information about and file system snapshots, including technical papers, you can visit Marshall Kirk McKusick's website at http://www.mckusick.com. File System Quotas accounting disk space disk quotas Quotas are an optional feature of the operating system that allow you to limit the amount of disk space and/or the number of files a user or members of a group may allocate on a per-file system basis. This is used most often on timesharing systems where it is desirable to limit the amount of resources any one user or group of users may allocate. This will prevent one user or group of users from consuming all of the available disk space. Configuring Your System to Enable Disk Quotas Before attempting to use disk quotas, it is necessary to make sure that quotas are configured in your kernel. This is done by adding the following line to your kernel configuration file: options QUOTA The stock GENERIC kernel does not have this enabled by default, so you will have to configure, build and install a custom kernel in order to use disk quotas. Please refer to for more information on kernel configuration. Next you will need to enable disk quotas in /etc/rc.conf. This is done by adding the line: enable_quotas="YES" disk quotas checking For finer control over your quota startup, there is an additional configuration variable available. Normally on bootup, the quota integrity of each file system is checked by the &man.quotacheck.8; program. The &man.quotacheck.8; facility insures that the data in the quota database properly reflects the data on the file system. This is a very time consuming process that will significantly affect the time your system takes to boot. If you would like to skip this step, a variable in /etc/rc.conf is made available for the purpose: check_quotas="NO" If you are running FreeBSD prior to 3.2-RELEASE, the configuration is simpler, and consists of only one variable. Set the following in your /etc/rc.conf: check_quotas="YES" Finally you will need to edit /etc/fstab to enable disk quotas on a per-file system basis. This is where you can either enable user or group quotas or both for all of your file systems. To enable per-user quotas on a file system, add the option to the options field in the /etc/fstab entry for the file system you want to enable quotas on. For example: /dev/da1s2g /home ufs rw,userquota 1 2 Similarly, to enable group quotas, use the option instead of . To enable both user and group quotas, change the entry as follows: /dev/da1s2g /home ufs rw,userquota,groupquota 1 2 By default, the quota files are stored in the root directory of the file system with the names quota.user and quota.group for user and group quotas respectively. See &man.fstab.5; for more information. Even though the &man.fstab.5; manual page says that you can specify an alternate location for the quota files, this is not recommended because the various quota utilities do not seem to handle this properly. At this point you should reboot your system with your new kernel. /etc/rc will automatically run the appropriate commands to create the initial quota files for all of the quotas you enabled in /etc/fstab, so there is no need to manually create any zero length quota files. In the normal course of operations you should not be required to run the &man.quotacheck.8;, &man.quotaon.8;, or &man.quotaoff.8; commands manually. However, you may want to read their manual pages just to be familiar with their operation. Setting Quota Limits disk quotas limits Once you have configured your system to enable quotas, verify that they really are enabled. An easy way to do this is to run: &prompt.root; quota -v You should see a one line summary of disk usage and current quota limits for each file system that quotas are enabled on. You are now ready to start assigning quota limits with the &man.edquota.8; command. You have several options on how to enforce limits on the amount of disk space a user or group may allocate, and how many files they may create. You may limit allocations based on disk space (block quotas) or number of files (inode quotas) or a combination of both. Each of these limits are further broken down into two categories: hard and soft limits. hard limit A hard limit may not be exceeded. Once a user reaches his hard limit he may not make any further allocations on the file system in question. For example, if the user has a hard limit of 500 blocks on a file system and is currently using 490 blocks, the user can only allocate an additional 10 blocks. Attempting to allocate an additional 11 blocks will fail. soft limit Soft limits, on the other hand, can be exceeded for a limited amount of time. This period of time is known as the grace period, which is one week by default. If a user stays over his or her soft limit longer than the grace period, the soft limit will turn into a hard limit and no further allocations will be allowed. When the user drops back below the soft limit, the grace period will be reset. The following is an example of what you might see when you run the &man.edquota.8; command. When the &man.edquota.8; command is invoked, you are placed into the editor specified by the EDITOR environment variable, or in the vi editor if the EDITOR variable is not set, to allow you to edit the quota limits. &prompt.root; edquota -u test Quotas for user test: /usr: blocks in use: 65, limits (soft = 50, hard = 75) inodes in use: 7, limits (soft = 50, hard = 60) /usr/var: blocks in use: 0, limits (soft = 50, hard = 75) inodes in use: 0, limits (soft = 50, hard = 60) You will normally see two lines for each file system that has quotas enabled. One line for the block limits, and one line for inode limits. Simply change the value you want updated to modify the quota limit. For example, to raise this user's block limit from a soft limit of 50 and a hard limit of 75 to a soft limit of 500 and a hard limit of 600, change: /usr: blocks in use: 65, limits (soft = 50, hard = 75) to: /usr: blocks in use: 65, limits (soft = 500, hard = 600) The new quota limits will be in place when you exit the editor. Sometimes it is desirable to set quota limits on a range of UIDs. This can be done by use of the option on the &man.edquota.8; command. First, assign the desired quota limit to a user, and then run edquota -p protouser startuid-enduid. For example, if user test has the desired quota limits, the following command can be used to duplicate those quota limits for UIDs 10,000 through 19,999: &prompt.root; edquota -p test 10000-19999 For more information see &man.edquota.8; manual page. Checking Quota Limits and Disk Usage disk quotas checking You can use either the &man.quota.1; or the &man.repquota.8; commands to check quota limits and disk usage. The &man.quota.1; command can be used to check individual user or group quotas and disk usage. A user may only examine his own quota, and the quota of a group he is a member of. Only the super-user may view all user and group quotas. The &man.repquota.8; command can be used to get a summary of all quotas and disk usage for file systems with quotas enabled. The following is some sample output from the quota -v command for a user that has quota limits on two file systems. Disk quotas for user test (uid 1002): Filesystem blocks quota limit grace files quota limit grace /usr 65* 50 75 5days 7 50 60 /usr/var 0 50 75 0 50 60 grace period On the /usr file system in the above example, this user is currently 15 blocks over the soft limit of 50 blocks and has 5 days of the grace period left. Note the asterisk * which indicates that the user is currently over his quota limit. Normally file systems that the user is not using any disk space on will not show up in the output from the &man.quota.1; command, even if he has a quota limit assigned for that file system. The option will display those file systems, such as the /usr/var file system in the above example. Quotas over NFS NFS Quotas are enforced by the quota subsystem on the NFS server. The &man.rpc.rquotad.8; daemon makes quota information available to the &man.quota.1; command on NFS clients, allowing users on those machines to see their quota statistics. Enable rpc.rquotad in /etc/inetd.conf like so: rquotad/1 dgram rpc/udp wait root /usr/libexec/rpc.rquotad rpc.rquotad Now restart inetd: &prompt.root; kill -HUP `cat /var/run/inetd.pid` Lucky Green Contributed by
shamrock@cypherpunks.to
 Encrypting Disk Partitions disks encrypting FreeBSD offers excellent online protections against unauthorized data access. File permissions and Mandatory Access Control (MAC) (see ) help prevent unauthorized third-parties from accessing data while the operating system is active and the computer is powered up. However, the permissions enforced by the operating system are irrelevant if an attacker has physical access to a computer and can simply move the computer's hard drive to another system to copy and analyze the sensitive data. Regardless of how an attacker may have come into possession of a hard drive or powered-down computer, GEOM Based Disk Encryption (gbde) can protect the data on the computer's file systems against even highly-motivated attackers with significant resources. Unlike cumbersome encryption methods that encrypt only individual files, gbde transparently encrypts entire file systems. No cleartext ever touches the hard drive's platter. Enabling gbde in the Kernel Become <username>root</username> Configuring gbde requires super-user privileges. &prompt.user; su - Password: Verify the Operating System Version &man.gbde.4; requires FreeBSD 5.0 or higher. &prompt.root; uname -r 5.0-RELEASE Add &man.gbde.4; Support to the Kernel Configuration File Using your favorite text editor, add the following line to your kernel configuration file: options GEOM_BDE Configure, recompile, and install the FreeBSD kernel. This process is described in . Reboot into the new kernel. Preparing the Encrypted Hard Drive The following example assumes that you are adding a new hard drive to your system that will hold a single encrypted partition. This partition will be mounted as /private. gbde can also be used to encrypt /home and /var/mail, but this requires more complex instructions which exceed the scope of this introduction. Add the New Hard Drive Install the new drive to the system as explained in . For the purposes of this example, a new hard drive partition has been added as /dev/ad4s1c. The /dev/ad0s1* devices represent existing standard FreeBSD partitions on the example system. &prompt.root; ls /dev/ad* /dev/ad0 /dev/ad0s1b /dev/ad0s1e /dev/ad4s1 /dev/ad0s1 /dev/ad0s1c /dev/ad0s1f /dev/ad4s1c /dev/ad0s1a /dev/ad0s1d /dev/ad4 Create a Directory to Hold gbde Lock Files &prompt.root; mkdir /etc/gbde The gbde lock file contains information that gbde requires to access encrypted partitions. Without access to the lock file, gbde will not be able to decrypt the data contained in the encrypted partition without significant manual intervention which is not supported by the software. Each encrypted partition uses a separate lock file. Initialize the gbde Partition A gbde partition must be initialized before it can be used. This initialization needs to be performed only once: &prompt.root; gbde init /dev/ad4s1c -i -L /etc/gbde/ad4s1c &man.gbde.8; will open your editor, permitting you to set various configuration options in a template. For use with UFS1 or UFS2, set the sector_size to 2048: $FreeBSD: src/sbin/gbde/template.txt,v 1.1 2002/10/20 11:16:13 phk Exp $ # # Sector size is the smallest unit of data which can be read or written. # Making it too small decreases performance and decreases available space. # Making it too large may prevent filesystems from working. 512 is the # minimum and always safe. For UFS, use the fragment size # sector_size = 2048 [...] &man.gbde.8; will ask you twice to type the passphrase that should be used to secure the data. The passphrase must be the same both times. gbde's ability to protect your data depends entirely on the quality of the passphrase that you choose. For tips on how to select a secure passphrase that is easy to remember, see the Diceware Passphrase website. The gbde init command creates a lock file for your gbde partition that in this example is stored as /etc/gbde/ad4s1c. gbde lock files must be backed up together with the contents of any encrypted partitions. While deleting a lock file alone cannot prevent a determined attacker from decrypting a gbde partition, without the lock file, the legitimate owner will be unable to access the data on the encrypted partition without a significant amount of work that is totally unsupported by &man.gbde.8; and its designer. Attach the Encrypted Partition to the Kernel &prompt.root; gbde attach /dev/ad4s1c -l /etc/gbde/ad4s1c You will be asked to provide the passphrase that you selected during the initialization of the encrypted partition. The new encrypted device will show up in /dev as /dev/device_name.bde: &prompt.root; ls /dev/ad* /dev/ad0 /dev/ad0s1b /dev/ad0s1e /dev/ad4s1 /dev/ad0s1 /dev/ad0s1c /dev/ad0s1f /dev/ad4s1c /dev/ad0s1a /dev/ad0s1d /dev/ad4 /dev/ad4s1c.bde Create a File System on the Encrypted Device Once the encrypted device has been attached to the kernel, you can create a file system on the device. To create a file system on the encrypted device, use &man.newfs.8;. Since it is much faster to initialize a new UFS2 file system than it is to initialize the old UFS1 file system, using &man.newfs.8; with the option is recommended. The option is the default with &os; 5.1-RELEASE and later. &prompt.root; newfs -U -O2 /dev/ad4s1c.bde The &man.newfs.8; command must be performed on an attached gbde partition which is identified by a *.bde extension to the device name. Mount the Encrypted Partition Create a mount point for the encrypted file system. &prompt.root; mkdir /private Mount the encrypted file system. &prompt.root; mount /dev/ad4s1c.bde /private Verify That the Encrypted File System is Available The encrypted file system should now be visible to &man.df.1; and be available for use. &prompt.user; df -H Filesystem Size Used Avail Capacity Mounted on /dev/ad0s1a 1037M 72M 883M 8% / /devfs 1.0K 1.0K 0B 100% /dev /dev/ad0s1f 8.1G 55K 7.5G 0% /home /dev/ad0s1e 1037M 1.1M 953M 0% /tmp /dev/ad0s1d 6.1G 1.9G 3.7G 35% /usr /dev/ad4s1c.bde 150G 4.1K 138G 0% /private Mounting Existing Encrypted File Systems After each boot, any encrypted file systems must be re-attached to the kernel, checked for errors, and mounted, before the file systems can be used. The required commands must be executed as user root. Attach the gbde Partition to the Kernel &prompt.root; gbde attach /dev/ad4s1c -l /etc/gbde/ad4s1c You will be asked to provide the passphrase that you selected during initialization of the encrypted gbde partition. Check the File System for Errors Since encrypted file systems cannot yet be listed in /etc/fstab for automatic mounting, the file systems must be checked for errors by running &man.fsck.8; manually before mounting. &prompt.root; fsck -p -t ffs /dev/ad4s1c.bde Mount the Encrypted File System &prompt.root; mount /dev/ad4s1c.bde /private The encrypted file system is now available for use. Automatically Mounting Encrypted Partitions It is possible to create a script to automatically attach, check, and mount an encrypted partition, but for security reasons the script should not contain the &man.gbde.8; password. Instead, it is recommended that such scripts be run manually while providing the password via the console or &man.ssh.1;. Cryptographic Protections Employed by gbde &man.gbde.8; encrypts the sector payload using 128-bit AES in CBC mode. Each sector on the disk is encrypted with a different AES key. For more information on gbde's cryptographic design, including how the sector keys are derived from the user-supplied passphrase, see &man.gbde.4;. Compatibility Issues &man.sysinstall.8; is incompatible with gbde-encrypted devices. All *.bde devices must be detached from the kernel before starting &man.sysinstall.8; or it will crash during its initial probing for devices. To detach the encrypted device used in our example, use the following command: &prompt.root; gbde detach /dev/ad4s1c Also note that, as &man.vinum.4; does not use the &man.geom.4; subsystem, you cannot use gbde with vinum volumes. diff --git a/en_US.ISO8859-1/books/handbook/mail/chapter.sgml b/en_US.ISO8859-1/books/handbook/mail/chapter.sgml index 7aa5139f22..ee227ac600 100644 --- a/en_US.ISO8859-1/books/handbook/mail/chapter.sgml +++ b/en_US.ISO8859-1/books/handbook/mail/chapter.sgml @@ -1,2284 +1,2284 @@ Bill Lloyd Original work by Jim Mock Rewritten by Electronic Mail Synopsis email electronic mail Electronic Mail, better known as email, is one of the most widely used forms of communication today. This chapter provides a basic introduction to running a mail server on &os;, as well as an introduction to sending and receiving email using &os;; however, it is not a complete reference and in fact many important considerations are omitted. For more complete coverage of the subject, the reader is referred to the many excellent books listed in . After reading this chapter, you will know: What software components are involved in sending and receiving electronic mail. Where basic sendmail configuration files are located in FreeBSD. An understanding of the difference between remote and local mailboxes. How to block spammers from illegally using your mail server as a relay. How to install and configure an alternate mail transfer agent on your system, replacing sendmail. How to troubleshoot common mail server problems. How to use SMTP with UUCP. How to set up the system to send mail only. How to use mail with a dialup connection. How to configure SMTP Authentication for added security. How to install and use a Mail User Agent, such as mutt to send and receive email. How to download your mail from a remote POP or IMAP server. How to automatically apply filters and rules to incoming email. Before reading this chapter, you should: Properly set up your network connection (). Properly set up the DNS information for your mail host (). Know how to install additional third-party software (). Using Electronic Mail POP IMAP DNS There are five major parts involved in an email exchange. They are: the user program, the server daemon, DNS, a remote or local mailbox, and of course, the mailhost itself. The User Program This includes command line programs such as mutt, pine, elm, and mail, and GUI programs such as balsa, xfmail to name a few, and something more sophisticated like a WWW browser. These programs simply pass off the email transactions to the local mailhost, either by calling one of the server daemons available, or delivering it over TCP. Mailhost Server Daemon mail server daemons sendmail mail server daemons postfix mail server daemons qmail mail server daemons exim &os; ships with sendmail by default, but also support numerous other mail server daemons, just some of which include: exim; postfix; qmail. The server daemon usually has two functions—it is responsible for receiving incoming mail as well as delivering outgoing mail. It is not responsible for the collection of mail using protocols such as POP or IMAP to read your email, nor does it allow connecting to local mbox or Maildir mailboxes. You may require an additional daemon for that. Older versions of sendmail have some serious security issues which may result in an attacker gaining local and/or remote access to your machine. Make sure that you are running a current version to avoid these problems. Optionally, install an alternative MTA from the &os; Ports Collection. Email and DNS The Domain Name System (DNS) and its daemon named play a large role in the delivery of email. In order to deliver mail from your site to another, the server daemon will look up the remote site in the DNS to determine the host that will receive mail for the destination. This process also occurs when mail is sent from a remote host to your mail server. DNS is responsible for mapping hostnames to IP addresses, as well as for storing information specific to mail delivery, known as MX records. The MX (Mail eXchanger) record specifies which host, or hosts, will recieve mail for a particular domain. If you do not have an MX record for your hostname or domain, the mail will be delivered directly to your host provided you have an A record pointing your hostname to your IP address. You may view the MX records for any domain by using the &man.host.1; command, as seen in the example below: &prompt.user; host -t mx FreeBSD.org FreeBSD.org mail is handled (pri=10) by mx1.FreeBSD.org Receiving Mail email receiving Receiving mail for your domain is done by the mail host. It will collect all mail sent to your domain and store it either in mbox (the default method for storing mail) or Maildir format, depending on your configuration. Once mail has been stored, it may either be read locally using applications such as &man.mail.1; or mutt, or remotely accessed and collected using protocols such as POP or IMAP. This means that should you only wish to read mail locally, you are not required to install a POP or IMAP server. Accessing remote mailboxes using <acronym>POP</acronym> and <acronym>IMAP</acronym> POP IMAP In order to access mailboxes remotely, you are required to have access to a POP or IMAP server. These protocols allow users to connect to their mailboxes from remote locations with ease. Though both POP and IMAP allow users to remotely access mailboxes, IMAP offers many advantages, some of which are: IMAP can store messages on a remote server as well as fetch them. IMAP supports concurrent updates. IMAP can be extremely useful over low-speed links as it allows users to fetch the structure of messages without downloading them; it can also perform tasks such as searching on the server in order to minimize data transfer between clients and servers. In order to install a POP or IMAP server, the following steps should be performed: Choose an IMAP or POP server that best suits your needs. The following POP and IMAP servers are well known and serve as some good examples: qpopper; teapop; imap-uw; courier-imap; Install the POP or IMAP daemon of your choosing from the ports collection. Where required, modify /etc/inetd.conf to load the POP or IMAP server. It should be noted that both POP and IMAP transmit information, including username and password credentials in clear-text. This means that if you wish to secure the transmission of information across these protocols, you should consider tunneling sessions over &man.ssh.1;. See the &os; handbook for more information. Accessing local mailboxes Mailboxes may be accessed locally by directly utilizing MUA's on the server on which the mailbox resides. This can be done using applications such as mutt or &man.mail.1;. The Mail Host mail host The mail host is the name given to a server that is responsible for delivering and receiving mail for your host, and possibly your network. Christopher Shumway Contributed by <application>sendmail</application> Configuration sendmail &man.sendmail.8; is the default Mail Transfer Agent (MTA) in FreeBSD. sendmail's job is to accept mail from Mail User Agents (MUA) and deliver it to the appropriate mailer as defined by its configuration file. sendmail can also accept network connections and deliver mail to local mailboxes or deliver it to another program. sendmail uses the following configuration files: /etc/mail/access /etc/mail/aliases /etc/mail/local-host-names /etc/mail/mailer.conf /etc/mail/mailertable /etc/mail/sendmail.cf /etc/mail/virtusertable Filename Function /etc/mail/access sendmail access database file /etc/mail/aliases Mailbox aliases /etc/mail/local-host-names Lists of hosts sendmail accepts mail for /etc/mail/mailer.conf Mailer program configuration /etc/mail/mailertable Mailer delivery table /etc/mail/sendmail.cf sendmail master configuration file /etc/mail/virtusertable Virtual users and domain tables <filename>/etc/mail/access</filename> The access database defines what host(s) or IP addresses have access to the local mail server and what kind of access they have. Hosts can be listed as , , or simply passed to sendmail's error handling routine with a given mailer error. Hosts that are listed as , which is the default, are allowed to send mail to this host as long as the mail's final destination is the local machine. Hosts that are listed as are rejected for all mail connections. Hosts that have the option for their hostname are allowed to send mail for any destination through this mail server. Configuring the <application>sendmail</application> Access Database cyberspammer.com 550 We don't accept mail from spammers FREE.STEALTH.MAILER@ 550 We don't accept mail from spammers another.source.of.spam REJECT okay.cyberspammer.com OK 128.32 RELAY In this example we have five entries. Mail senders that match the left hand side of the table are affected by the action on the right side of the table. The first two examples give an error code to sendmail's error handling routine. The message is printed to the remote host when a mail matches the left hand side of the table. The next entry rejects mail from a specific host on the Internet, another.source.of.spam. The next entry accepts mail connections from a host okay.cyberspammer.com, which is more exact than the cyberspammer.com line above. More specific matches override less exact matches. The last entry allows relaying of electronic mail from hosts with an IP address that begins with 128.32. These hosts would be able to send mail through this mail server that are destined for other mail servers. When this file is updated, you need to run make in /etc/mail/ to update the database. <filename>/etc/mail/aliases</filename> The aliases database contains a list of virtual mailboxes that are expanded to other user(s), files, programs or other aliases. Here are a few examples that can be used in /etc/mail/aliases: Mail Aliases root: localuser ftp-bugs: joe,eric,paul bit.bucket: /dev/null procmail: "|/usr/local/bin/procmail" The file format is simple; the mailbox name on the left side of the colon is expanded to the target(s) on the right. The first example simply expands the mailbox root to the mailbox localuser, which is then looked up again in the aliases database. If no match is found, then the message is delivered to the local user localuser. The next example shows a mail list. Mail to the mailbox ftp-bugs is expanded to the three local mailboxes joe, eric, and paul. Note that a remote mailbox could be specified as user@example.com. The next example shows writing mail to a file, in this case /dev/null. The last example shows sending mail to a program, in this case the mail message is written to the standard input of /usr/local/bin/procmail through a &unix; pipe. When this file is updated, you need to run make in /etc/mail/ to update the database. <filename>/etc/mail/local-host-names</filename> This is a list of hostnames &man.sendmail.8; is to accept as the local host name. Place any domains or hosts that sendmail is to be receiving mail for. For example, if this mail server was to accept mail for the domain example.com and the host mail.example.com, its local-host-names might look something like this: example.com mail.example.com When this file is updated, &man.sendmail.8; needs to be restarted to read the changes. <filename>/etc/mail/sendmail.cf</filename> sendmail's master configuration file, sendmail.cf controls the overall behavior of sendmail, including everything from rewriting e-mail addresses to printing rejection messages to remote mail servers. Naturally, with such a diverse role, this configuration file is quite complex and its details are a bit out of the scope of this section. Fortunately, this file rarely needs to be changed for standard mail servers. The master sendmail configuration file can be built from &man.m4.1; macros that define the features and behavior of sendmail. Please see /usr/src/contrib/sendmail/cf/README for some of the details. When changes to this file are made, sendmail needs to be restarted for the changes to take effect. <filename>/etc/mail/virtusertable</filename> The virtusertable maps mail addresses for virtual domains and mailboxes to real mailboxes. These mailboxes can be local, remote, aliases defined in /etc/mail/aliases or files. Example Virtual Domain Mail Map root@example.com root postmaster@example.com postmaster@noc.example.net @example.com joe In the above example, we have a mapping for a domain example.com. This file is processed in a first match order down the file. The first item maps root@example.com to the local mailbox root. The next entry maps postmaster@example.com to the mailbox postmaster on the host noc.example.net. Finally, if nothing from example.com has matched so far, it will match the last mapping, which matches every other mail message addressed to someone at example.com. This will be mapped to the local mailbox joe. Andrew Boothman Written by Gregory Neil Shapiro Information taken from e-mails written by Changing Your Mail Transfer Agent email change mta As already mentioned, FreeBSD comes with sendmail already installed as your MTA (Mail Transfer Agent). Therefore by default it is in charge of your outgoing and incoming mail. However, for a variety of reasons, some system administrators want to change their system's MTA. These reasons range from simply wanting to try out another MTA to needing a specific feature or package which relies on another mailer. Fortunately, whatever the reason, FreeBSD makes it easy to make the change. Install a New MTA You have a wide choice of MTAs available. A good starting point is the FreeBSD Ports Collection where you will be able to find many. Of course you are free to use any MTA you want from any location, as long as you can make it run under FreeBSD. Start by installing your new MTA. Once it is installed it gives you a chance to decide if it really fulfills your needs, and also gives you the opportunity to configure your new software before getting it to take over from sendmail. When doing this, you should be sure that installing the new software will not attempt to overwrite system binaries such as /usr/bin/sendmail. Otherwise, your new mail software has essentially been put into service before you have configured it. Please refer to your chosen MTA's documentation for information on how to configure the software you have chosen. Disable <application>sendmail</application> The procedure used to start sendmail changed significantly between 4.5-RELEASE and 4.6-RELEASE. Therefore, the procedure used to disable it is subtly different. FreeBSD 4.5-STABLE before 2002/4/4 and Earlier (Including 4.5-RELEASE and Earlier) Enter: sendmail_enable="NO" into /etc/rc.conf. This will disable sendmail's incoming mail service, but if /etc/mail/mailer.conf (see below) is not changed, sendmail will still be used to send e-mail. FreeBSD 4.5-STABLE after 2002/4/4 (Including 4.6-RELEASE and Later) In order to completely disable sendmail you must use sendmail_enable="NONE" in /etc/rc.conf. If you disable sendmail's outgoing mail service in this way, it is important that you replace it with a fully working alternative mail delivery system. If you choose not to, system functions such as &man.periodic.8; will be unable to deliver their results by e-mail as they would normally expect to. Many parts of your system may expect to have a functional sendmail-compatible system. If applications continue to use sendmail's binaries to try to send e-mail after you have disabled them, mail could go into an inactive sendmail queue, and never be delivered. If you only want to disable sendmail's incoming mail service, you should set sendmail_enable="NO" in /etc/rc.conf. More information on sendmail's startup options is available from the &man.rc.sendmail.8; manual page. Running Your New MTA on Boot You may have a choice of two methods for running your new MTA on boot, again depending on what version of FreeBSD you are running. FreeBSD 4.5-STABLE before 2002/4/11 (Including 4.5-RELEASE and Earlier) Add a script to /usr/local/etc/rc.d/ that ends in .sh and is executable by root. The script should accept start and stop parameters. At startup time the system scripts will execute the command /usr/local/etc/rc.d/supermailer.sh start which you can also use to manually start the server. At shutdown time, the system scripts will use the stop option, running the command /usr/local/etc/rc.d/supermailer.sh stop which you can also use to manually stop the server while the system is running. FreeBSD 4.5-STABLE after 2002/4/11 (Including 4.6-RELEASE and Later) With later versions of FreeBSD, you can use the above method or you can set mta_start_script="filename" in /etc/rc.conf, where filename is the name of some script that you want executed at boot to start your MTA. Replacing <application>sendmail</application> as the System's Default Mailer The program sendmail is so ubiquitous as standard software on &unix; systems that some software just assumes it is already installed and configured. For this reason, many alternative MTA's provide their own compatible implementations of the sendmail command-line interface; this facilitates using them as drop-in replacements for sendmail. Therefore, if you are using an alternative mailer, you will need to make sure that software trying to execute standard sendmail binaries such as /usr/bin/sendmail actually executes your chosen mailer instead. Fortunately, FreeBSD provides a system called &man.mailwrapper.8; that does this job for you. When sendmail is operating as installed, you will find something like the following in /etc/mail/mailer.conf: sendmail /usr/libexec/sendmail/sendmail send-mail /usr/libexec/sendmail/sendmail mailq /usr/libexec/sendmail/sendmail newaliases /usr/libexec/sendmail/sendmail hoststat /usr/libexec/sendmail/sendmail purgestat /usr/libexec/sendmail/sendmail This means that when any of these common commands (such as sendmail itself) are run, the system actually invokes a copy of mailwrapper named sendmail, which checks mailer.conf and executes /usr/libexec/sendmail/sendmail instead. This system makes it easy to change what binaries are actually executed when these default sendmail functions are invoked. Therefore if you wanted /usr/local/supermailer/bin/sendmail-compat to be run instead of sendmail, you could change /etc/mail/mailer.conf to read: sendmail /usr/local/supermailer/bin/sendmail-compat send-mail /usr/local/supermailer/bin/sendmail-compat mailq /usr/local/supermailer/bin/mailq-compat newaliases /usr/local/supermailer/bin/newaliases-compat hoststat /usr/local/supermailer/bin/hoststat-compat purgestat /usr/local/supermailer/bin/purgestat-compat Finishing Once you have everything configured the way you want it, you should either kill the sendmail processes that you no longer need and start the processes belonging to your new software, or simply reboot. Rebooting will also give you the opportunity to ensure that you have correctly configured your system to start your new MTA automatically on boot. Troubleshooting email troubleshooting Why do I have to use the FQDN for hosts on my site? You will probably find that the host is actually in a different domain; for example, if you are in foo.bar.edu and you wish to reach a host called mumble in the bar.edu domain, you will have to refer to it by the fully-qualified domain name, mumble.bar.edu, instead of just mumble. BIND Traditionally, this was allowed by BSD BIND resolvers. However the current version of BIND that ships with FreeBSD no longer provides default abbreviations for non-fully qualified domain names other than the domain you are in. So an unqualified host mumble must either be found as mumble.foo.bar.edu, or it will be searched for in the root domain. This is different from the previous behavior, where the search continued across mumble.bar.edu, and mumble.edu. Have a look at RFC 1535 for why this was considered bad practice, or even a security hole. As a good workaround, you can place the line: search foo.bar.edu bar.edu instead of the previous: domain foo.bar.edu into your /etc/resolv.conf. However, make sure that the search order does not go beyond the boundary between local and public administration, as RFC 1535 calls it. sendmail says mail loops back to myself This is answered in the sendmail FAQ as follows: I'm getting these error messages: 553 MX list for domain.net points back to relay.domain.net 554 <user@domain.net>... Local configuration error How can I solve this problem? You have asked mail to the domain (e.g., domain.net) to be forwarded to a specific host (in this case, relay.domain.net) by using an MX record, but the relay machine does not recognize itself as domain.net. Add domain.net to /etc/mail/local-host-names [known as /etc/sendmail.cw prior to version 8.10] (if you are using FEATURE(use_cw_file)) or add Cw domain.net to /etc/mail/sendmail.cf. The sendmail FAQ can be found at and is recommended reading if you want to do any tweaking of your mail setup. PPP How can I run a mail server on a dial-up PPP host? You want to connect a FreeBSD box on a LAN to the Internet. The FreeBSD box will be a mail gateway for the LAN. The PPP connection is non-dedicated. UUCP There are at least two ways to do this. One way is to use UUCP. Another way is to get a full-time Internet server to provide secondary MX services for your domain. For example, if your company's domain is example.com and your Internet service provider has set example.net up to provide secondary MX services to your domain: example.com. MX 10 example.com. MX 20 example.net. Only one host should be specified as the final recipient (add Cw example.com in /etc/mail/sendmail.cf on example.com). When the sending sendmail is trying to deliver the mail it will try to connect to you (example.com) over the modem link. It will most likely time out because you are not online. The program sendmail will automatically deliver it to the secondary MX site, i.e. your Internet provider (example.net). The secondary MX site will then periodically try to connect to your host and deliver the mail to the primary MX host (example.com). You might want to use something like this as a login script: #!/bin/sh # Put me in /usr/local/bin/pppmyisp ( sleep 60 ; /usr/sbin/sendmail -q ) & /usr/sbin/ppp -direct pppmyisp If you are going to create a separate login script for a user you could use sendmail -qRexample.com instead in the script above. This will force all mail in your queue for example.com to be processed immediately. A further refinement of the situation is as follows: Message stolen from the &a.isp;. > we provide the secondary MX for a customer. The customer connects to > our services several times a day automatically to get the mails to > his primary MX (We do not call his site when a mail for his domains > arrived). Our sendmail sends the mailqueue every 30 minutes. At the > moment he has to stay 30 minutes online to be sure that all mail is > gone to the primary MX. > > Is there a command that would initiate sendmail to send all the mails > now? The user has not root-privileges on our machine of course. In the privacy flags section of sendmail.cf, there is a definition Opgoaway,restrictqrun Remove restrictqrun to allow non-root users to start the queue processing. You might also like to rearrange the MXs. We are the 1st MX for our customers like this, and we have defined: # If we are the best MX for a host, try directly instead of generating # local config error. OwTrue That way a remote site will deliver straight to you, without trying the customer connection. You then send to your customer. Only works for hosts, so you need to get your customer to name their mail machine customer.com as well as hostname.customer.com in the DNS. Just put an A record in the DNS for customer.com. Why do I keep getting Relaying Denied errors when sending mail from other hosts? In default FreeBSD installations, sendmail is configured to only send mail from the host it is running on. For example, if a POP server is available, then users will be able to check mail from school, work, or other remote locations but they still will not be able to send outgoing emails from outside locations. Typically, a few moments after the attempt, an email will be sent from MAILER-DAEMON with a 5.7 Relaying Denied error message. There are several ways to get around this. The most straightforward solution is to put your ISP's address in a relay-domains file at /etc/mail/relay-domains. A quick way to do this would be: &prompt.root; echo "your.isp.example.com" > /etc/mail/relay-domains After creating or editing this file you must restart sendmail. This works great if you are a server administrator and do not wish to send mail locally, or would like to use a point and click client/system on another machine or even another ISP. It is also very useful if you only have one or two email accounts set up. If there is a large number of addresses to add, you can simply open this file in your favorite text editor and then add the domains, one per line: your.isp.example.com other.isp.example.net users-isp.example.org www.example.org Now any mail sent through your system, by any host in this list (provided the user has an account on your system), will succeed. This is a very nice way to allow users to send mail from your system remotely without allowing people to send SPAM through your system. Advanced Topics The following section covers more involved topics such as mail configuration and setting up mail for your entire domain. Basic Configuration email configuration Out of the box, you should be able to send email to external hosts as long as you have set up /etc/resolv.conf or are running your own name server. If you would like to have mail for your host delivered to the MTA (e.g., sendmail) on your own FreeBSD host, there are two methods: Run your own name server and have your own domain. For example, FreeBSD.org Get mail delivered directly to your host. This is done by delivering mail directly to the current DNS name for your machine. For example, example.FreeBSD.org. SMTP Regardless of which of the above you choose, in order to have mail delivered directly to your host, it must have a permanent static IP address (not a dynamic address, as with most PPP dial-up configurations). If you are behind a firewall, it must pass SMTP traffic on to you. If you want to receive mail directly at your host, you need to be sure of either of two things: MX record Make sure that the (lowest-numbered) MX record in your DNS points to your host's IP address. Make sure there is no MX entry in your DNS for your host. Either of the above will allow you to receive mail directly at your host. Try this: &prompt.root; hostname example.FreeBSD.org &prompt.root; host example.FreeBSD.org example.FreeBSD.org has address 204.216.27.XX If that is what you see, mail directly to yourlogin@example.FreeBSD.org should work without problems (assuming sendmail is running correctly on example.FreeBSD.org). If instead you see something like this: &prompt.root; host example.FreeBSD.org example.FreeBSD.org has address 204.216.27.XX example.FreeBSD.org mail is handled (pri=10) by hub.FreeBSD.org All mail sent to your host (example.FreeBSD.org) will end up being collected on hub under the same username instead of being sent directly to your host. The above information is handled by your DNS server. The DNS record that carries mail routing information is the Mail eXchange entry. If no MX record exists, mail will be delivered directly to the host by way of its IP address. The MX entry for freefall.FreeBSD.org at one time looked like this: freefall MX 30 mail.crl.net freefall MX 40 agora.rdrop.com freefall MX 10 freefall.FreeBSD.org freefall MX 20 who.cdrom.com As you can see, freefall had many MX entries. The lowest MX number is the host that receives mail directly if available; if it is not accessible for some reason, the others (sometimes called backup MXes) accept messages temporarily, and pass it along when a lower-numbered host becomes available, eventually to the lowest-numbered host. Alternate MX sites should have separate Internet connections from your own in order to be most useful. Your ISP or another friendly site should have no problem providing this service for you. Mail for Your Domain In order to set up a mailhost (a.k.a. mail server) you need to have any mail sent to various workstations directed to it. Basically, you want to claim any mail for any hostname in your domain (in this case *.FreeBSD.org) and divert it to your mail server so your users can receive their mail on the master mail server. DNS To make life easiest, a user account with the same username should exist on both machines. Use &man.adduser.8; to do this. The mailhost you will be using must be the designated mail exchanger for each workstation on the network. This is done in your DNS configuration like so: example.FreeBSD.org A 204.216.27.XX ; Workstation MX 10 hub.FreeBSD.org ; Mailhost This will redirect mail for the workstation to the mailhost no matter where the A record points. The mail is sent to the MX host. You cannot do this yourself unless you are running a DNS server. If you are not, or cannot run your own DNS server, talk to your ISP or whoever provides your DNS. If you are doing virtual email hosting, the following information will come in handy. For this example, we will assume you have a customer with his own domain, in this case customer1.org, and you want all the mail for customer1.org sent to your mailhost, mail.myhost.com. The entry in your DNS should look like this: customer1.org MX 10 mail.myhost.com You do not need an A record for customer1.org if you only want to handle email for that domain. Be aware that pinging customer1.org will not work unless an A record exists for it. The last thing that you must do is tell sendmail on your mailhost what domains and/or hostnames it should be accepting mail for. There are a few different ways this can be done. Either of the following will work: Add the hosts to your /etc/mail/local-host-names file if you are using the FEATURE(use_cw_file). If you are using a version of sendmail earlier than 8.10, the file is /etc/sendmail.cw. Add a Cwyour.host.com line to your /etc/sendmail.cf or /etc/mail/sendmail.cf if you are using sendmail 8.10 or higher. SMTP with UUCP The sendmail configuration that ships with FreeBSD is designed for sites that connect directly to the Internet. Sites that wish to exchange their mail via UUCP must install another sendmail configuration file. Tweaking /etc/mail/sendmail.cf manually is an advanced topic. sendmail version 8 generates config files via &man.m4.1; preprocessing, where the actual configuration occurs on a higher abstraction level. The &man.m4.1; configuration files can be found under /usr/src/usr.sbin/sendmail/cf. If you did not install your system with full sources, the sendmail configuration set has been broken out into a separate source distribution tarball. Assuming you have your FreeBSD source code CDROM mounted, do: &prompt.root; cd /cdrom/src &prompt.root; cat scontrib.?? | tar xzf - -C /usr/src/contrib/sendmail This extracts to only a few hundred kilobytes. The file README in the cf directory can serve as a basic introduction to &man.m4.1; configuration. The best way to support UUCP delivery is to use the mailertable feature. This creates a database that sendmail can use to make routing decisions. First, you have to create your .mc file. The directory /usr/src/usr.sbin/sendmail/cf/cf contains a few examples. Assuming you have named your file foo.mc, all you need to do in order to convert it into a valid sendmail.cf is: &prompt.root; cd /usr/src/usr.sbin/sendmail/cf/cf &prompt.root; make foo.cf &prompt.root; cp foo.cf /etc/mail/sendmail.cf A typical .mc file might look like: VERSIONID(`Your version number') OSTYPE(bsd4.4) FEATURE(accept_unresolvable_domains) FEATURE(nocanonify) FEATURE(mailertable, `hash -o /etc/mail/mailertable') define(`UUCP_RELAY', your.uucp.relay) define(`UUCP_MAX_SIZE', 200000) define(`confDONT_PROBE_INTERFACES') MAILER(local) MAILER(smtp) MAILER(uucp) Cw your.alias.host.name Cw youruucpnodename.UUCP The lines containing accept_unresolvable_domains, nocanonify, and confDONT_PROBE_INTERFACES features will prevent any usage of the DNS during mail delivery. The UUCP_RELAY clause is needed to support UUCP delivery. Simply put an Internet hostname there that is able to handle .UUCP pseudo-domain addresses; most likely, you will enter the mail relay of your ISP there. Once you have this, you need an /etc/mail/mailertable file. If you have only one link to the outside that is used for all your mails, the following file will suffice: # # makemap hash /etc/mail/mailertable.db < /etc/mail/mailertable . uucp-dom:your.uucp.relay A more complex example might look like this: # # makemap hash /etc/mail/mailertable.db < /etc/mail/mailertable # horus.interface-business.de uucp-dom:horus .interface-business.de uucp-dom:if-bus interface-business.de uucp-dom:if-bus .heep.sax.de smtp8:%1 horus.UUCP uucp-dom:horus if-bus.UUCP uucp-dom:if-bus . uucp-dom: The first three lines handle special cases where domain-addressed mail should not be sent out to the default route, but instead to some UUCP neighbor in order to shortcut the delivery path. The next line handles mail to the local Ethernet domain that can be delivered using SMTP. Finally, the UUCP neighbors are mentioned in the .UUCP pseudo-domain notation, to allow for a uucp-neighbor !recipient override of the default rules. The last line is always a single dot, matching everything else, with UUCP delivery to a UUCP neighbor that serves as your universal mail gateway to the world. All of the node names behind the uucp-dom: keyword must be valid UUCP neighbors, as you can verify using the command uuname. As a reminder that this file needs to be converted into a DBM database file before use. The command line to accomplish this is best placed as a comment at the top of the mailertable file. You always have to execute this command each time you change your mailertable file. Final hint: if you are uncertain whether some particular mail routing would work, remember the option to sendmail. It starts sendmail in address test mode; simply enter 3,0, followed by the address you wish to test for the mail routing. The last line tells you the used internal mail agent, the destination host this agent will be called with, and the (possibly translated) address. Leave this mode by typing CtrlD. &prompt.user; sendmail -bt ADDRESS TEST MODE (ruleset 3 NOT automatically invoked) Enter <ruleset> <address> > 3,0 foo@example.com canonify input: foo @ example . com ... parse returns: $# uucp-dom $@ your.uucp.relay $: foo < @ example . com . > > ^D Bill Moran Contributed by Setting up to send only There are many instances where you may only want to send mail through a relay. Some examples are: Your computer is a desktop machine, but you want to use programs such as &man.send-pr.1;. To do so, you should use your ISP's mail relay. The computer is a server that does not handle mail locally, but needs to pass off all mail to a relay for processing. Just about any MTA is capable of filling this particular niche. Unfortunately, it can be very difficult to properly configure a full-featured MTA just to handle offloading mail. Programs such as sendmail and postfix are largely overkill for this use. Additionally, if you are using a typical Internet access service, your agreement may forbid you from running a mail server. The easiest way to fulfill those needs is to install the mail/ssmtp port. Execute the following commands as root: - &prompt.root; cd /usr/ports/mail/ssmtp - &prompt.root; make install replace clean + &prompt.root; cd /usr/ports/mail/ssmtp +&prompt.root; make install replace clean Once installed, mail/ssmtp can be configured with a four-line file located at /usr/local/etc/ssmtp/ssmtp.conf: root=yourrealemail@example.com mailhub=mail.example.com rewriteDomain=example.com hostname=_HOSTNAME_ Make sure you use your real email address for root. Enter your ISP's outgoing mail relay in place of mail.example.com (some ISPs call this the outgoing mail server or SMTP server). Make sure you disable sendmail by setting sendmail_enable="NONE" in /etc/rc.conf. mail/ssmtp has some other options available. See the example configuration file in /usr/local/etc/ssmtp or the manual page of ssmtp for some examples and more information. Setting up ssmtp in this manner will allow any software on your computer that needs to send mail to function properly, while not violating your ISP's usage policy or allowing your computer to be hijacked for spamming. Using Mail with a Dialup Connection If you have a static IP address, you should not need to adjust anything from the defaults. Set your host name to your assigned Internet name and sendmail will do the rest. If you have a dynamically assigned IP number and use a dialup PPP connection to the Internet, you will probably have a mailbox on your ISPs mail server. Let's assume your ISP's domain is example.net, and that your user name is user, you have called your machine bsd.home, and your ISP has told you that you may use relay.example.net as a mail relay. In order to retrieve mail from your mailbox, you must install a retrieval agent. The fetchmail utility is a good choice as it supports many different protocols. This program is available as a package or from the ports collection (mail/fetchmail). Usually, your ISP will provide POP. If you are using user PPP, you can automatically fetch your mail when an Internet connection is established with the following entry in /etc/ppp/ppp.linkup: MYADDR: !bg su user -c fetchmail If you are using sendmail (as shown below) to deliver mail to non-local accounts, you probably want to have sendmail process your mailqueue as soon as your Internet connection is established. To do this, put this command after the fetchmail command in /etc/ppp/ppp.linkup: !bg su user -c "sendmail -q" Assume that you have an account for user on bsd.home. In the home directory of user on bsd.home, create a .fetchmailrc file: poll example.net protocol pop3 fetchall pass MySecret This file should not be readable by anyone except user as it contains the password MySecret. In order to send mail with the correct from: header, you must tell sendmail to use user@example.net rather than user@bsd.home. You may also wish to tell sendmail to send all mail via relay.example.net, allowing quicker mail transmission. The following .mc file should suffice: VERSIONID(`bsd.home.mc version 1.0') OSTYPE(bsd4.4)dnl FEATURE(nouucp)dnl MAILER(local)dnl MAILER(smtp)dnl Cwlocalhost Cwbsd.home MASQUERADE_AS(`example.net')dnl FEATURE(allmasquerade)dnl FEATURE(masquerade_envelope)dnl FEATURE(nocanonify)dnl FEATURE(nodns)dnl define(`SMART_HOST', `relay.example.net') Dmbsd.home define(`confDOMAIN_NAME',`bsd.home')dnl define(`confDELIVERY_MODE',`deferred')dnl Refer to the previous section for details of how to turn this .mc file into a sendmail.cf file. Also, do not forget to restart sendmail after updating sendmail.cf. James Gorham Written by SMTP Authentication Having SMTP Authentication in place on your mail server has a number of benefits. SMTP Authentication can add another layer of security to sendmail, and has the benefit of giving mobile users who switch hosts the ability to use the same mail server without the need to reconfigure their mail client settings each time. Install security/cyrus-sasl from the ports. You can find this port in security/cyrus-sasl. security/cyrus-sasl has a number of compile time options to choose from and, for the method we will be using here, make sure to select the option. After installing security/cyrus-sasl, edit /usr/local/lib/sasl/Sendmail.conf (or create it if it does not exist) and add the following line: pwcheck_method: passwd This method will enable sendmail to authenticate against your FreeBSD passwd database. This saves the trouble of creating a new set of usernames and passwords for each user that needs to use SMTP authentication, and keeps the login and mail password the same. Now edit /etc/make.conf and add the following lines: SENDMAIL_CFLAGS=-I/usr/local/include/sasl1 -DSASL SENDMAIL_LDFLAGS=-L/usr/local/lib SENDMAIL_LDADD=-lsasl These lines will give sendmail the proper configuration options for linking to cyrus-sasl at compile time. Make sure that cyrus-sasl has been installed before recompiling sendmail. Recompile sendmail by executing the following commands: &prompt.root; cd /usr/src/usr.sbin/sendmail &prompt.root; make cleandir &prompt.root; make obj &prompt.root; make &prompt.root; make install The compile of sendmail should not have any problems if /usr/src has not been changed extensively and the shared libraries it needs are available. After sendmail has been compiled and reinstalled, edit your /etc/mail/freebsd.mc file (or whichever file you use as your .mc file. Many administrators choose to use the output from &man.hostname.1; as the .mc file for uniqueness). Add these lines to it: dnl set SASL options TRUST_AUTH_MECH(`GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN')dnl define(`confAUTH_MECHANISMS', `GSSAPI DIGEST-MD5 CRAM-MD5 LOGIN')dnl define(`confDEF_AUTH_INFO', `/etc/mail/auth-info')dnl These options configure the different methods available to sendmail for authenticating users. If you would like to use a method other than pwcheck, please see the included documentation. Finally, run &man.make.1; while in /etc/mail. That will run your new .mc file and create a .cf file named freebsd.cf (or whatever name you have used for your .mc file). Then use the command make install restart, which will copy the file to sendmail.cf, and will properly restart sendmail. For more information about this process, you should refer to /etc/mail/Makefile. If all has gone correctly, you should be able to enter your login information into the mail client and send a test message. For further investigation, set the of sendmail to 13 and watch /var/log/maillog for any errors. You may wish to add the following lines to /etc/rc.conf so this service will be available after every system boot: sasl_pwcheck_enable="YES" sasl_pwcheck_program="/usr/local/sbin/pwcheck" This will ensure the initialization of SMTP_AUTH upon system boot. For more information, please see the sendmail page regarding SMTP authentication. Marc Silver Contributed by Mail User Agents Mail User Agents A Mail User Agent (MUA) is an application that is used to send and receive email. Furthermore, as email evolves and becomes more complex, MUA's are becoming increasingly powerful in the way they interact with email; this gives users increased functionality and flexibility. &os; contains support for numerous mail user agents, all of which can be easily installed using the FreeBSD Ports Collection. Users may choose between graphical email clients such as evolution or balsa; console based clients such as mutt, pine or mail; or the web interfaces used by some large organizations. mail &man.mail.1; is the default Mail User Agent (MUA) in &os;. It's a console based MUA that offers all the basic functionality required to send and receive text-based email, though it is limited in interaction abilities with attachments and can only support local mailboxes. Although mail does not natively support interaction with POP or IMAP servers, these mailboxes may be downloaded to a local mbox file using an application such as fetchmail, which will be discussed later in this chapter. In order to send and receive email, simply invoke the mail command as per the following example: &prompt.user; mail The contents of the user mailbox in /var/mail/ are automatically read by the mail utility. Should the mailbox be empty, the utility exits with a message indicating that no mails could be found. Once the mailbox has been read, the application interface is started, and a list of messages will be displayed. Messages are automatically numbered, as can be seen in the following example: Mail version 8.1 6/6/93. Type ? for help. "/var/mail/marcs": 3 messages 3 new >N 1 root@localhost Mon Mar 8 14:05 14/510 "test" N 2 root@localhost Mon Mar 8 14:05 14/509 "user account" N 3 root@localhost Mon Mar 8 14:05 14/509 "sample" Messages can now be read by using the t mail command, suffixed by the message number that should be displayed. In this example, we will read the first email: & t 1 Message 1: From root@localhost Mon Mar 8 14:05:52 2004 X-Original-To: marcs@localhost Delivered-To: marcs@localhost To: marcs@localhost Subject: test Date: Mon, 8 Mar 2004 14:05:52 +0200 (SAST) From: root@localhost (Charlie Root) This is a test message, please reply if you receive it. As can be seen in the example above, the t key will cause the message to be displayed with full headers. To display the list of messages again, the h key should be used. If the email requires a response, you may use mail to reply, by using either the R or r mail keys. The R key instructs mail to reply only to the sender of the email, while r replies not only to the sender, but also to other recipients of the message. You may also suffix these commands with the mail number which you would like make a reply to. Once this has been done, the response should be entered, and the end of the message should be marked by a single . on a new line. An example can be seen below: & R 1 To: root@localhost Subject: Re: test Thank you, I did get your email. . EOT In order to send new email, the m key should be used, followed by the recipient email address. Multiple recipients may also be specified by separating each address with the , delimiter. The subject of the message may then be entered, followed by the message contents. The end of the message should be specified by putting a single . on a new line. & mail root@localhost Subject: I mastered mail Now I can send and receive email using mail ... :) . EOT While inside the mail utility, the ? command may be used to display help at any time. The &man.mail.1; manual page should also be consulted for more help with mail. As previously mentioned, the &man.mail.1; command was not originally designed to handle attachments, and thus deals with them very poorly. Newer MUA's such as mutt handle attachments in a much more intelligent way. But should you still wish to use the mail command, the converters/mpack port may be of considerable use. mutt mutt is a small yet very powerful Mail User Agent, with excellent features, just some of which include: The ability to thread messages; PGP support for digital signing and encryption of email; MIME Support; Maildir Support; Highly customizable. All of these features help to make mutt one of the most advanced mail user agents available. See http://www.mutt.org for more information on mutt. The stable version of mutt may be installed using the mail/mutt port, while the current development version may be installed via the mail/mutt-devel port. After the port has been installed, mutt can be started by issuing the following command: &prompt.user; mutt mutt will automatically read the contents of the user mailbox in /var/mail and display the contents if applicable. If no mails are found in the user mailbox, then mutt will wait for commands from the user. The example below shows mutt displaying a list of messages. In order to read an email, simply select it using the cursor keys, and press the Enter key. An example of mutt displaying email can be seen below: As with the &man.mail.1; command, mutt allows users to reply only to the sender of the message as well as to all recipients. To reply only to the sender of the email, use the r keyboard shortcut. To send a group reply, which will be sent to the original sender as well as all the message recipients, use the g shortcut. mutt makes use of the &man.vi.1; command as an editor for creating and replying to emails. This may be customized by the user by creating or editing their own .muttrc and setting the variable. In order to compose a new mail message, press m. After a valid subject has been given, mutt will start &man.vi.1; and the mail can be written. Once the contents of the mail are complete, save and quit from vi and mutt will resume, displaying a summary screen of the mail that is to be delivered. In order to send the mail, press y. An example of the summary screen can be seen below: mutt also contains extensive help, which can be accessed from most of the menus by pressing the ? key. The top line also displays the keyboard shortcuts where appropriate. pine pine is aimed at a beginner user, but also includes some advanced features. The pine software has had several remote vulnerabilities discovered in the past, which allowed remote attackers to execute arbitrary code as users on the local system, by the action of sending a specially-prepared email. All such known problems have been fixed, but the pine code is written in a very insecure style and the &os; Security Officer believes there are likely to be other undiscovered vulnerabilities. You install pine at your own risk. The current version of pine may be installed using the mail/pine4 port. Once the port has installed, pine can be started by issuing the following command: &prompt.user; pine The first time that pine is run it displays a greeting page with a brief introduction, as well as a request from the pine development team to send an anonymous email message allowing them to judge how many users are using their client. To send this anonymous message, press Enter, or alternatively press E to exit the greeting without sending an anonymous message. An example of the greeting page can be seen below: Users are then presented with the main menu, which can be easily navigated using the cursor keys. This main menu provides shortcuts for the composing new mails, browsing of mail directories, and even the administration of address book entries. Below the main menu, relevant keyboard shortcuts to perform functions specific to the task at hand are shown. The default directory opened by pine is the inbox. To view the message index, press I, or select the MESSAGE INDEX option as seen below: The message index shows messages in the current directory, and can be navigated by using the cursor keys. Highlighted messages can be read by pressing the Enter key. In the screenshot below, a sample message is displayed by pine. Keyboard shortcuts are displayed as a reference at the bottom of the screen. An example of one of these shortcuts is the r key, which tells the MUA to reply to the current message being displayed. Replying to an email in pine is done using the pico editor, which is installed by default with pine. The pico utility makes it easy to navigate around the message and is slightly more forgiving on novice users than &man.vi.1; or &man.mail.1;. Once the reply is complete, the message can be sent by pressing CtrlX . The pine application will ask for confirmation. The pine application can be customized using the option from the main menu. Consult http://www.washington.edu/pine/ for more information. Marc Silver Contributed by Using fetchmail Using fetchmail fetchmail is a full-featured IMAP and POP client which allows users to automatically download mail from remote IMAP and POP servers and into local mailboxes; there it can be accessed more easily. fetchmail can be installed using the mail/fetchmail port, and offers various features, some of which include: Support of POP3, APOP, KPOP, IMAP, ETRN and ODMR protocols. Ability to forward mail using SMTP, which allows filtering, forwarding, and aliasing to function normally. May be run in daemon mode to check periodically for new messages. Can retrieve multiple mailboxes and forward them based on configuration, to different local users. While it is outside the scope of this document to explain all of fetchmail's features, some basic features will be explained. The fetchmail utility requires a configuration file known as .fetchmailrc, in order to run correctly. This file includes server information as well as login credentials. Due to the sensitive nature of the contents of this file, it is advisable to make it read-only, by issuing the following command: &prompt.user; chmod 600 .fetchmailrc The following .fetchmailrc serves as an example for downloading a single user mailbox using POP. It tells fetchmail to connect to example.com using a username of joesoap and a password of XXX. This example assumes that the user joesoap is also a user on the local system. poll example.com protocol pop3 username "joesoap" password "XXX" The next example connects to multiple POP and IMAP servers and redirects to different local usernames where applicable. poll example.com proto pop3: user "joesoap", with password "XXX", is "jsoap" here; user "andrea", with password "XXXX"; poll example2.net proto imap: user "john", with password "XXXXX", is "myth" here; The fetchmail utility can be run in daemon mode by running it with the flag, followed by the interval (in seconds) that fetchmail should poll servers listed in the .fetchmailrc file. The following example would cause fetchmail to poll every 60 seconds: &prompt.user; fetchmail -d 60 More information on fetchmail can be found at http://www.catb.org/~esr/fetchmail/. Marc Silver Contributed by Using procmail Using procmail The procmail utility is an incredibly powerful application used to filter incoming mail. It allows users to define rules which can be matched to incoming mails to perform specific functions or to reroute mail to alternative mailboxes and/or email addresses. procmail can be installed using the mail/procmail port. Once installed, it can be directly integrated into most MTA's; consult your MTA documentation for more information. Alternatively, procmail can be integrated by adding the following line to a .forward in the home directory of the user utilizing procmail features. "|exec /usr/local/bin/procmail || exit 75" The following section will display some basic procmail rules, as well as brief descriptions on what they do. These rules, and others must be inserted into a .procmailrc file, which must reside in a user's the home directory. The majority of these rules can also be found in the &man.procmailex.5; manual page. Forward all mail from user@example.com to an external address of goodmail@example2.com: :0 * ^From.*user@example.com ! goodmail@example2.com Forward all mails shorter than 1000 bytes to an external address of goodmail@example2.com: :0 * < 1000 ! goodmail@example2.com Send all mail sent to alternate@example.com into a mailbox called alternate: :0 * ^TOalternate@example.com alternate Send all mail with a subject of Spam to /dev/null: :0 ^Subject:.*Spam /dev/null A useful recipe that parses incoming &os;.org mailing lists and places each list in its own mailbox: :0 * ^Sender:.owner-freebsd-\/[^@]+@FreeBSD.ORG { LISTNAME=${MATCH} :0 * LISTNAME??^\/[^@]+ FreeBSD-${MATCH} }