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diff --git a/en_US.ISO8859-1/books/handbook/backups/chapter.sgml b/en_US.ISO8859-1/books/handbook/backups/chapter.sgml deleted file mode 100644 index f7c05d2731..0000000000 --- a/en_US.ISO8859-1/books/handbook/backups/chapter.sgml +++ /dev/null @@ -1,731 +0,0 @@ -<chapter id="backups"> - <title>Backups</title> - - <para>Issues of hardware compatibility are among the most troublesome in the - computer industry today and FreeBSD is by no means immune to trouble. In - this respect, FreeBSD's advantage of being able to run on inexpensive - commodity PC hardware is also its liability when it comes to support for - the amazing variety of components on the market. While it would be - impossible to provide a exhaustive listing of hardware that FreeBSD - supports, this section serves as a catalog of the device drivers included - with FreeBSD and the hardware each drivers supports. Where possible and - appropriate, notes about specific products are included. You may also want - to refer to <link linkend="kernelconfig-config"> the kernel configuration - file</link> section in this handbook for a list of supported - devices.</para> - - <para>As FreeBSD is a volunteer project without a funded testing department, - we depend on you, the user, for much of the information contained in this - catalog. If you have direct experience of hardware that does or does not - work with FreeBSD, please let us know by sending e-mail to the &a.doc;. - Questions about supported hardware should be directed to the &a.questions - (see <link linkend="eresources-mail">Mailing Lists</link> for more - information). When submitting information or asking a question, please - remember to specify exactly what version of FreeBSD you are using and - include as many details of your hardware as possible.</para> - - <sect1> - <title>* What about backups to floppies?</title> - - <para></para> - </sect1> - - <sect1 id="backups-tapebackups"> - <title>Tape Media</title> - - <para>The major tape media are the 4mm, 8mm, QIC, mini-cartridge and - DLT.</para> - - <sect2 id="backups-tapebackups-4mm"> - <title>4mm (DDS: Digital Data - Storage)</title> - - <para>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.</para> - - <para>Data thruput on these drives starts ~150kB/s, peaking at ~500kB/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.</para> - - <para>4mm drives, like 8mm drives, use helical-scan. All the benefits - and drawbacks of helical-scan apply to both 4mm and 8mm drives.</para> - - <para>Tapes should be retired from use after 2,000 passes or 100 full - backups.</para> - </sect2> - - <sect2 id="backups-tapebackups-8mm"> - <title>8mm (Exabyte)</title> - - <para>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.</para> - - <para>Data thruput ranges from ~250kB/s to ~500kB/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.</para> - - <para>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.</para> - </sect2> - - <sect2 id="backups-tapebackups-qic"> - <title>QIC</title> - - <para>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 - <emphasis>most</emphasis> 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). <link linkend="backups-tapebackups-mini">Mini-cartridges</link>, - which also use 1/4" wide tape are discussed separately. Tape libraries - and changers are not available.</para> - - <para>Data thruput ranges from ~150kB/s to ~500kB/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.</para> - - <para>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).</para> - - <para>Tapes should be retired from use after 5,000 backups.</para> - </sect2> - - <sect2 id="backups-tapebackups-mini"> - <title>* Mini-Cartridge</title> - - <para></para> - </sect2> - - <sect2 id="backups-tapebackups-dlt"> - <title>DLT</title> - - <para>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.</para> - - <para>Data thruput is approximately 1.5MB/s, three times the thruput of - 4mm, 8mm, or QIC tape drives. Data capacities range from 10GB to 20GB - 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 50GB to 9TB of - storage.</para> - - <para>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.</para> - </sect2> - - <sect2> - <title>Using a new tape for the first time</title> - - <para>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:</para> - -<informalexample> - <screen>st0(ncr1:4:0): NOT READY asc:4,1 -st0(ncr1:4:0): Logical unit is in process of becoming ready</screen> - </informalexample> - - <para>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:</para> - - <para><command>mt fsf 1</command> causes the tape drive to write an - Identifier Block to the tape.</para> - - <para>Use the front panel button to eject the tape.</para> - - <para>Re-insert the tape and - <citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> data to the tape.</para> - - <para><citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum></citerefentry> will report <literal>DUMP: - End of tape detected</literal> and the console will show: - <literal>HARDWARE FAILURE info:280 asc:80,96</literal></para> - - <para>rewind the tape using: <command>mt rewind</command></para> - - <para>Subsequent tape operations are successful.</para> - </sect2> - </sect1> - - <sect1 id="backup-programs"> - <title>Backup Programs</title> - - <para>The three major programs are - <citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>, - <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum></citerefentry>, - and - <citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum></citerefentry>.</para> - - <sect2> - <title>Dump and Restore</title> - - <para><citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> and <citerefentry> - <refentrytitle>restore</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> are the traditional Unix backup programs. They operate - on the drive as a collection of disk blocks, below the abstractions of - files, links and directories that are created by the filesystems. - <citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> backs up devices, entire filesystems, not parts of a - filesystem and not directory trees that span more than one filesystem, - using either soft links <citerefentry> - <refentrytitle>ln</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> or mounting one filesystem onto another. - <citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> does not write files and directories to tape, but - rather writes the data blocks that are the building blocks of files - and directories. <citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> has quirks that remain from its early days in - Version 6 of ATT 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.</para> - - <para><citerefentry> - <refentrytitle>rdump</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> and <citerefentry> - <refentrytitle>rrestore</refentrytitle> - <manvolnum>8</manvolnum></citerefentry> backup data across the - network to a tape drive attached to another computer. Both programs - rely upon <citerefentry> - <refentrytitle>rcmd</refentrytitle> - <manvolnum>3</manvolnum> - </citerefentry> and <citerefentry> - <refentrytitle>ruserok</refentrytitle> - <manvolnum>3</manvolnum></citerefentry> to access the remote tape - drive. Therefore, the user performing the backup must have - <literal>rhosts</literal> access to the remote computer. The - arguments to <citerefentry> - <refentrytitle>rdump</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> and <citerefentry> - <refentrytitle>rrestore</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry> must suitable to use on the remote computer. (e.g. - When <command>rdump</command>'ing from a FreeBSD computer to an - Exabyte tape drive connected to a Sun called - <hostid>komodo</hostid>, use: <command>/sbin/rdump 0dsbfu 54000 - 13000 126 komodo:/dev/nrst8 /dev/rsd0a 2>&1</command>) Beware: - there are security implications to allowing <literal>rhosts</literal> - commands. Evaluate your situation carefully.</para> - </sect2> - - <sect2> - <title>Tar</title> - - <para><citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> also dates back to Version 6 of ATT Unix (circa - 1975). <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> operates in cooperation with the filesystem; - <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> writes files and directories to tape. - <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> does not support the full range of options that are - available from <citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum></citerefentry>, but <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> does not require the - unusual command pipeline that <citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> uses.</para> - - <para>Most versions of <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> do not support backups across the network. The GNU - version of <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum></citerefentry>, which FreeBSD utilizes, - supports remote devices using the same syntax as - <command>rdump</command>. To <citerefentry> - <refentrytitle>tar</refentrytitle> - <manvolnum>1</manvolnum> - </citerefentry> to an Exabyte tape drive connected to a Sun called - komodo, use: <command>/usr/bin/tar cf komodo:/dev/nrst8 . - 2>&1</command>. For versions without remote device support, - you can use a pipeline and <citerefentry> - <refentrytitle>rsh</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> to send the data to a - remote tape drive. (XXX add an example command)</para> - </sect2> - - <sect2> - <title>Cpio</title> - - <para><citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> is the original Unix - file interchange tape program for magnetic media. <citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> has options (among many - others) to perform byte-swapping, write a number of different - archives format, and pipe the data to other programs. This last - feature makes <citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> and excellent choice for - installation media. <citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> does not know how to walk - the directory tree and a list of files must be provided thru - <filename>STDIN</filename>.</para> - - <para><citerefentry> - <refentrytitle>cpio</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> does not support backups - across the network. You can use a pipeline and <citerefentry> - <refentrytitle>rsh</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> to send the data to a - remote tape drive. (XXX add an example command)</para> - </sect2> - - <sect2> - <title>Pax</title> - - <para><citerefentry> - <refentrytitle>pax</refentrytitle> - <manvolnum>1</manvolnum></citerefentry> is IEEE/POSIX's answer to - <command>tar</command> and <command>cpio</command>. Over the years the - various versions of <command>tar</command> and <command>cpio</command> - have gotten slightly incompatible. So rather than fight it out to - fully standardize them, POSIX created a new archive utility. - <command>pax</command> attempts to read and write many of the various - cpio and tar formats, plus new formats of its own. Its command set - more resembles <command>cpio</command> than - <command>tar</command>.</para> - </sect2> - - <sect2 id="backups-programs-amanda"> - <title>Amanda</title> - - <para><ulink url="../ports/misc.html#amanda-2.4.0">Amanda</ulink> - (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 network communications with the Amanda server. A common problem at - locations with a number of large disks is 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 filesystems 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 filesystems listed in Amanda's - configuration file. The "archive set" also contains nightly - incremental (or differential) backups of all the filesystems. - Restoring a damaged filesystem requires the most recent full backup - and the incremental backups.</para> - - <para>The configuration file provides fine control 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.</para> - </sect2> - - <sect2> - <title>Do nothing</title> - - <para>“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!</para> - - <para>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.</para> - - <para>“Do nothing” is the correct backup method for - <filename>/usr/obj</filename> and other directory trees that can be - exactly recreated by your computer. An example is the files that - comprise these handbook pages-they have been generated from - <acronym>SGML</acronym> input files. Creating backups of these - <acronym>HTML</acronym> files is not necessary. The - <acronym>SGML</acronym> source files are backed up regularly.</para> - </sect2> - - <sect2> - <title>Which Backup Program is Best?</title> - - <para><citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum></citerefentry> <emphasis>Period.</emphasis> - 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 filesystems is <citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>. Elizabeth created - filesystems containing a large variety of unusual conditions (and some - not so unusual ones) and tested each program by do a backup and - restore of that filesystems. 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 <ulink - url="http://reality.sgi.com/zwicky_neu/testdump.doc.html">torture-testing Backup and Archive Programs</ulink>.</para> - </sect2> - - <sect2> - <title>Emergency Restore Procedure</title> - - <sect3> - <title>Before the Disaster</title> - - <para>There are only four steps that you need to perform in - preparation for any disaster that may occur.</para> - - <para>First, print the disklabel from each of your disks - (<command>e.g. disklabel sd0 | lpr</command>), your filesystem table - (<command>/etc/fstab</command>) and all boot messages, two copies of - each.</para> - - <para>Second, determine that the boot and fixit floppies - (<filename>boot.flp</filename> and <filename>fixit.flp</filename>) - 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.</para> - - <para>Otherwise, you have to create two custom bootable floppies - which has a kernel that can mount your all of your disks and - access your tape drive. These floppies must contain: - <citerefentry> - <refentrytitle>fdisk</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>, <citerefentry> - <refentrytitle>disklabel</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>, <citerefentry> - <refentrytitle>newfs</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>, <citerefentry> - <refentrytitle>mount</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>, and whichever backup - program you use. These programs must be statically linked. If you - use <citerefentry> - <refentrytitle>dump</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>, the floppy must contain - <citerefentry> - <refentrytitle>restore</refentrytitle> - <manvolnum>8</manvolnum></citerefentry>.</para> - - <para>Third, create backup tapes regularly. Any changes that you make - after your last backup may be irretrievably lost. Write-protect the - backup tapes.</para> - - <para>Fourth, test the floppies (either <filename>boot.flp</filename> - and <filename>fixit.flp</filename> 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 <command>tar xvf /dev/rst0</command>, you might - accidently type <command>tar cvf /dev/rst0</command> and over-write - your backup tape).</para> - - <para>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.</para> - - <para>An example script for creating a bootable floppy:</para> - - <programlisting> -<![ CDATA [#!/bin/sh -# -# create a restore floppy -# -# format the floppy -# -PATH=/bin:/sbin:/usr/sbin:/usr/bin - -fdformat -q fd0 -if [ $? -ne 0 ] -then - echo "Bad floppy, please use a new one" - exit 1 -fi - -# place boot blocks on the floppy -# -disklabel -w -B -b /usr/mdec/fdboot -s /usr/mdec/bootfd /dev/rfd0c fd1440 - -# -# newfs the one and only partition -# -newfs -t 2 -u 18 -l 1 -c 40 -i 5120 -m 5 -o space /dev/rfd0a - -# -# mount the new floppy -# -mount /dev/fd0a /mnt - -# -# create required directories -# -mkdir /mnt/dev -mkdir /mnt/bin -mkdir /mnt/sbin -mkdir /mnt/etc -mkdir /mnt/root -mkdir /mnt/mnt # for the root partition -mkdir /mnt/tmp -mkdir /mnt/var - -# -# populate the directories -# -if [ ! -x /sys/compile/MINI/kernel ] -then - cat << EOM -The MINI kernel does not exist, please create one. -Here is an example config file: -# -# MINI -- A kernel to get FreeBSD on onto a disk. -# -machine "i386" -cpu "I486_CPU" -ident MINI -maxusers 5 - -options INET # needed for _tcp _icmpstat _ipstat - # _udpstat _tcpstat _udb -options FFS #Berkeley Fast File System -options FAT_CURSOR #block cursor in syscons or pccons -options SCSI_DELAY=15 #Be pessimistic about Joe SCSI device -options NCONS=2 #1 virtual consoles -options USERCONFIG #Allow user configuration with -c XXX - -config kernel root on sd0 swap on sd0 and sd1 dumps on sd0 - -controller isa0 -controller pci0 - -controller fdc0 at isa? port "IO_FD1" bio irq 6 drq 2 vector fdintr -disk fd0 at fdc0 drive 0 - -controller ncr0 - -controller scbus0 - -device sc0 at isa? port "IO_KBD" tty irq 1 vector scintr -device npx0 at isa? port "IO_NPX" irq 13 vector npxintr - -device sd0 -device sd1 -device sd2 - -device st0 - -pseudo-device loop # required by INET -pseudo-device gzip # Exec gzipped a.out's -EOM - exit 1 -fi - -cp -f /sys/compile/MINI/kernel /mnt - -gzip -c -best /sbin/init > /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 sd0 -./MAKEDEV sd1 -./MAKEDEV sd2 -./MAKEDEV st0 -./MAKEDEV pty0 -cd / - -# -# create minimum filesystem table -# -cat > /mnt/etc/fstab <<EOM -/dev/fd0a / ufs rw 1 1 -EOM - -# -# create minimum passwd file -# -cat > /mnt/etc/passwd <<EOM -root:*:0:0:Charlie &:/root:/bin/sh -EOM - -cat > /mnt/etc/master.passwd <<EOM -root::0:0::0:0:Charlie &:/root:/bin/sh -EOM - -chmod 600 /mnt/etc/master.passwd -chmod 644 /mnt/etc/passwd -/usr/sbin/pwd_mkdb -d/mnt/etc /mnt/etc/master.passwd - -# -# umount the floppy and inform the user -# -/sbin/umount /mnt]]></programlisting> - </sect3> - - <sect3> - <title>After the Disaster</title> - - <para>The key question is: did your hardware survive? You have been - doing regular backups so there is no need to worry about the - software.</para> - - <para>If the hardware has been damaged. First, replace those parts - that have been damaged.</para> - - <para>If your hardware is okay, check your floppies. If you are using - a custom boot floppy, boot single-user (type <literal>-s</literal> - at the <prompt>boot:</prompt> prompt). Skip the following - paragraph.</para> - - <para>If you are using the <filename>boot.flp</filename> and - <filename>fixit.flp</filename> floppies, keep reading. Insert the - <filename>boot.flp</filename> floppy in the first floppy drive and - boot the computer. The original install menu will be displayed on - the screen. Select the <literal>Fixit--Repair mode with CDROM or - floppy.</literal> option. Insert the - <filename>fixit.flp</filename> when prompted. - <command>restore</command> and the other programs that you need are - located in <filename>/mnt2/stand</filename>.</para> - - <para>Recover each filesystem separately.</para> - - <para>Try to <citerefentry> - <refentrytitle>mount</refentrytitle> - <manvolnum>8</manvolnum> - </citerefentry>(e.g. <command>mount /dev/sd0a - /mnt</command>) the root partition of your first disk. If the - disklabel was damaged, use <citerefentry> - <refentrytitle>disklabel</refentrytitle> - <manvolnum>8</manvolnum></citerefentry> to re-partition and - label the disk to match the label that your printed and saved. Use - <citerefentry> - <refentrytitle>newfs</refentrytitle> - <manvolnum>8</manvolnum></citerefentry> to re-create the - filesystems. Re-mount the root partition of the floppy read-write - (<command>mount -u -o rw /mnt</command>). Use your backup program - and backup tapes to recover the data for this filesystem (e.g. - <command>restore vrf /dev/st0</command>). Unmount the filesystem - (e.g. <command>umount /mnt</command>) Repeat for each filesystem - that was damaged.</para> - - <para>Once your system is running, backup your data onto new tapes. - Whatever caused the crash or data loss may strike again. An another - hour spent now, may save you from further distress later.</para> - </sect3> - - <sect3> - <title>* I did not prepare for the Disaster, What Now?</title> - - <para></para> - </sect3> - </sect2> - </sect1> -</chapter> - -<!-- - Local Variables: - mode: sgml - sgml-declaration: "../chapter.decl" - sgml-indent-data: t - sgml-omittag: nil - sgml-always-quote-attributes: t - sgml-parent-document: ("../handbook.sgml" "part" "chapter") - End: ---> |