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             Chapter 19. Amanda FAQ
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Chapter 19. Amanda FAQ


Amanda Core Team

AMANDA Core Team

Stefan G. Weichinger

XML-conversion;Updates
AMANDA Core Team
<sgw@amanda.org>
This file contains answers to some questions that are frequently asked in the
Amanda mailing lists, specially by new users. Please take a look at this file
before posting, this can save us time that could be spent improving Amanda and
its documentation.
New entries and modifications are welcome; send them to mailto://amanda-
users@amanda.org or mailto://amanda-hackers@amanda.org.
You may also want to take a look at the Amanda FAQ-O-Matic http://
www.amanda.org/fom-serve/cache/1.html.


  Why_does_Amanda_fail_to_build_on_my_system?

  Why_does_amdump_report_that_all_disks_failed?

  Why_does_amcheck_say_"port_NNN_is_not_secure"?

  Why_does_amcheck_claim_that_the_tape_is_"not_an_Amanda_tape"?

  Why_does_amcheck_report_"selfcheck_request_timed_out"?

  Why_does_amandad.debug_contain_"error_receiving_message"?

  Why_does_amcheck_say_"access_as_<username>_not_allowed..."?

  Why_does_amcheck_report_"ip_address_#.#.#.#"_is_not_in_the_ip_list_list_for
  <hostname>'?

  Why_does_amcheck_say_"cannot_overwrite_active_tape"?

  Why_does_amcheck_tell_me_"DUMP_program_not_available"?

  Which_tape_changer_configuration_should_I_use_in_amanda.conf?

  Where_do_I_get_my_tapetype-definition_from?_Do_I_have_to_run_amtapetype?

  Should_I_use_software_or_hardware_compression?

  How_can_I_configure_Amanda_so_that_it_performs_full_backups_on_the_week-end
  and_incrementals_on_weekdays?

  What_if_my_tape_unit_uses_expensive_tapes,_and_I_don't_want_to_use_one_tape
  per_day?_Can't_Amanda_append_to_tapes?

  How_can_I_configure_Amanda_for_long-term_archiving?

  Can_I_backup_separate_disks_of_the_same_host_in_different_configurations?

  Can_Amanda_span_large_filesystems_across_multiple_tapes?

  What's_the_difference_between_option_"skip-full"_and_"strategy_nofull"?

  Why_does_amdump_report_"results_missing"?

  Why_does_amdump_report_"disk_offline"?

  What_if_amdump_reports_"dumps_way_too_big,_must_skip_incremental_dumps"?

  amdump_reported_"infofile_update_failed"._What_should_I_do?

  Why_does_Amanda_sometimes_promote_full_dumps?

  Why_does_amrecover_report_"no_index_records"_or_"disk_not_found"?

  Ok,_I'm_done_with_testing_Amanda,_now_I_want_to_put_it_in_production._How_can
  I_reset_its_databases_so_as_to_start_from_scratch?

  The_man-page_of_dump_says_that_active_filesystems_may_be_backed_up
  inconsistently._What_does_Amanda_do_to_prevent_inconsistent_backups?

  Which_version_of_GNU-tar_should_I_use?

  What_does_"bumping"_mean?

  How_do_I_backup_a_Windows_server?

  How_do_I_tell_my_iptables-based_firewall_to_allow_Amanda_through?

  How_do_I_get_rid_of_pressing_"q"_to_get_rid_of_a_pager_prompt_when_using
  amrecover?

  Is_there_a_way_to_tell_the_pager_that_my_terminal_has_"y"_lines?


 Why does Amanda fail to build on my system?
 One of the most common reasons for compile-time errors is stale information in
 config.cache, after a build on a different platform using the same build tree.
 In order to avoid this problem, make sure you don't ever reuse build trees
 across platforms, or at least run make distclean before running configure on
 another platform.
 Another common reason for failure, that causes link-time errors, is a problem
 in libtool that causes it to search for symbols in already-installed amanda
 libraries, instead of in the just-built ones. This problem is known to affect
 SunOS 4.1.3 and FreeBSD. You can usually work around it by specifying a
 different prefix when you configure the new version of Amanda. However, it may
 not work if the previous version of Amanda was installed in /usr/local and gcc
 searches this directory by default; in this case, you must either remove the
 old libraries (which you don't want to do, right? :-) or call configure with
 the flag --disable-libtool. In this case, Amanda won't create shared
 libraries, so binaries will be larger, but you may worry about that later.
 You may also want to take a look at Amanda_2.5.0_-_System-Specific
 Installation_Notes, as well as to the Amanda Patches Page (http://
 www.amanda.org/patches/) for other known problems. If everything fails, you
 should read the manual, but since we don't have one yet, just post a help
 request to the amanda-users mailing list (mailto://amanda-users@amanda.org),
 showing the last few lines of the failed build.
 Why does amdump report that all disks failed?
 Probably because the Amanda clients are not properly configured. Before you
 ever run amdump, make sure amcheck succeeds. When it does, so should amdump.
 Make sure you run amcheck as the same user that is supposed to start amdump,
 otherwise you may get incorrect results.
 Why does amcheck say "port NNN is not secure"?
 Because amcheck, as some other Amanda programs, must be installed as setuid-
 root. Run make install as "root", or chown all Amanda setuid programs to
 "root", then chown u+s them again, if chown drops the setuid bit.
 Why does amcheck claim that the tape is "not an Amanda tape"?
 Because Amanda requires you to label tapes before it uses them. Run amlabel in
 order to label a tape.
 If, even after labeling a tape, amcheck still complains about it, make sure
 the regular expression specified in amanda.conf matches the label you have
 specified, and check whether you have configured non-rewinding tape devices
 for Amanda to use. For example, use /dev/nrst0 instead of /dev/rst0, /dev/rmt/
 0bn instead of /dev/rmt/0b, or some other system-dependent device name that
 contains an "n", instead of one that does not. The "n" stands for non-
 rewinding.
 If you have labeled any tapes using the rewiding device configuration, you'll
 have to label them again.
 Why does amcheck report "selfcheck request timed out"?
 This can occur under several different situations. First, make sure this
 problem is repeatable; if Amanda programs are NFS-auto-mounted, some clients
 may fail to mount the Amanda binaries in time.
 If the error is repeatable, log into the client, and check whether the
 directory /tmp/amanda exists, and a file named amandad.debug exists in there:
 amandad will create this file whenever it starts. If this file does not exist,
 amandad is not starting properly, or it lacks permission to create /tmp/
 amanda/amandad.debug.
 In the latter case, wipe out /tmp/amanda, and amandad should create it next
 time it runs. In the former case, check your inetd configuration. Make sure
 you have added the Amanda services to /etc/services (or the NIS services map),
 that /etc/inetd.conf was properly configured, and that you have signalled
 inetd to reread this file (some systems may need rebooting). Check section 2.2
 from in the Amanda_Installation_Notes for details. Check the inetd man-page
 for possible differences between the standard format of /etc/inetd.conf and
 the one in your system.
 Pay special attention to typos in /etc/inetd.conf; error messages will
 probably appear in /var/adm/messages or /var/log/messages if you have typed
 the amandad program name incorrectly. Make sure the same user that you have
 specified at configure-time (configure --with-user=<USERNAME>) is listed in /
 etc/inetd.conf. Check whether this user has permission to run amandad, as well
 as any shared libraries amandad depends upon, by running the specified amandad
 command by hand, as the Amanda user. It should just time-out after 30 seconds
 waiting for a UDP packet. If you type anything, it will abort immediately,
 because it can't read a UDP packet from the keyboard.
 As soon as you have properly configured /etc/inetd.conf so as to run amandad,
 you should no longer get the "selfcheck request timed out" message. A nice
 tool to help make sure inetd is really listening on the amandad port is lsof,
 available at ftp://vic.cc.purdue.edu/pub/tools/unix/lsof.
 Why does amandad.debug contain "error receiving message"?
 One possibility is that you have run amandad from the command line prompt and
 typed anything instead of waiting for it to time-out: in this case, it will
 try to read a UDP packet from the keyboard, and this was reported not to work
 on most keyboards :-). However, if you have run amandad as any user other than
 the one listed in /etc/inetd.conf, it may have created a /tmp/amanda directory
 that the Amanda user cannot write to, so you should wipe it out.
 Another possibility is that the Amanda service was not properly configured as
 a UDP service; check /etc/services and /etc/inetd.conf.
 Why does amcheck say "access as <username> not allowed..."?
 There must be something wrong with .amandahosts configuration (or .rhosts, if
 you have configured --without-amandahosts).
 First, if the <username> is not what you expect (i.e., not what you have
 specified in the --with-user flag, at configure time), check the inetd
 configuration file: you must have specified the wrong username there.
 Make sure you specify the names exactly as they appear in the error message
 after the `@' sign in .amandahosts/.rhosts. You'll need a fully-qualified
 domain name or not, depending on how your client resolves IP addresses to host
 names.
 Why does amcheck report "ip address #.#.#.#" is not in the ip list list for
 <hostname>'?
 Check your DNS configuration tables. In order to avoid DNS-spoofing, Amanda
 double-checks hostname<->IP address mapping. If the IP address the request
 comes from maps to a hostname, but this hostname does not map back to the
 incoming IP address, the request is denied.
 Why does amcheck say "cannot overwrite active tape"?
 Because, if you configure Amanda to use N tapes, by setting tapecycle to N in
 amanda.conf, before Amanda overwrites a tape, it must write to at least other
 N-1 tapes. Of course, Amanda will always refuse to overwrite a tape marked for
 `noreuse' with amadmin. Furthermore, such tapes are not counted when Amanda
 computes `N-1' tapes.
 If, for some reason, you want to tell Amanda to overwrite a particular tape,
 regardless of its position in the cycle, use amrmtape. This command will
 remove this tape from the tapelist file, that is used to manage the tape
 cycle, and will delete information about backups stored in that tape from the
 Amanda database.
 Why does amcheck tell me "DUMP program not available"?
 Because configure could not find dump when it was first run. This is a common
 problem on Linux hosts, because most Linux distributions do not install dump
 by default.
 If you don't have a DUMP program installed, install it, remove config.cache,
 run configure again and rebuild Amanda. While configure is running, make sure
 it can find the installed DUMP program. If it cannot, you may have to set the
 environment variables DUMP and RESTORE by hand, before running configure.
 If you can't or don't want to install DUMP, you may use GNU tar, but make sure
 it as release 1.12 or newer; release 1.11.8 may work, but estimates will be
 slow as hell.
 Which tape changer configuration should I use in amanda.conf?
 If you only have one tape unit, you have two choices:

   i. Don't use a tape changer at all, i.e., set runtapes to 1, set tapedev to
      the non-rewinding device corresponding to the tape unit, and comment out
      tpchanger, changerfile and changerdev
  ii. Set up chg-manual, so that you can change tapes manually. If you select
      chg-manual, you will not be able to start amdump as a cron job, and you
      should always run amflush -f, because chg-manual will ask you to press
      return in the terminal where you started the controlling program.

 If you have several tape units, which you want to use to emulate a tape
 changer, you want chg-multi. Even if you do own a real tape changer, that
 operates based on ejecting a tape or such, chg-multi may be useful.
 Actual tape changers usually require specialized changer programs, such as
 mtx, chio or specific system calls. The availability of these programs is much
 more dependent on the operating system you're running than on the particular
 tape changer hardware you have.
 mtx, for example, is available for several platforms. However, even if you
 find it for your platform, beware that there exist several different programs
 named mtx, that require different command line arguments, and print different
 output, and Amanda's chg-mtx does not support them all. You may have to edit
 the script, which shouldn't be hard to do.
 In section BUILT-IN TAPE CHANGERS of Amanda_Tape_Changer_Support you will find
 details about the tape changer interfacing programs provided with Amanda, that
 can interact with common tape changer programs and with tape changer-related
 system calls provided by some operating system. If none of them matches your
 needs, you may have to develop your own tape changer interface script.
 Before posting a question to the Amanda mailing lists, *please* search the
 archives, and try to obtain as much information about driving your tape
 changer hardware from the vendor of the changer hardware and of the operating
 system, rather than from the Amanda mailing lists. We usually don't have much
 to say about tape changer units, and several questions about them remain
 unanswered. :-(
 Anyway, if you decide to post a question, make sure you specify both the tape
 changer hardware *and* the OS/platform that is going to interface with it.
 Good luck! :-)
 Where do I get my tapetype-definition from? Do I have to run amtapetype?
 It is not mandatory to run amtapetype at installation-time. It is very likely
 that your tapedrive or -changer is one of the devices that are already covered
 by one of the existing tapetype-definitions.
 You may find tapetype-definitions in the example amanda.conf, in the
 mailinglist-archives of the amanda-users-mailinglist at http://
 marc.theaimsgroup.com/?l=amanda-users or in the Amanda-FAQ-O-Matic at http://
 www.amanda.org/fom-serve/cache/1.html.
 Reasons to run amtapetype for your device:

 * You want to generate your own tapetype-definition because you can't find any
   suitable tapetype-definition for your device.
 * You want to determine the performance of your device.
 * You want to determine if your device has hardware-compression enabled.

 If you decide to run amtapetype, please refer to the chapter Tapetypes and the
 manpage amtapetype(8).
 Should I use software or hardware compression?
 When you enable software compression, you drastically reduce the compression
 that might be achieved by hardware. In fact, tape drives will usually use
 *more* tape if you tell them to try to further compress already compressed
 data.
 Thus, you must choose whether you're going to use software or hardware
 compression; don't ever enable both unless you want to waste tape space.
 Since Amanda prefers to have complete information about tape sizes and
 compression rates, it can do a better job if you use software compression.
 However, if you can't afford the extra CPU usage, Amanda can live with the
 unpredictability of hardware compression, but you'll have to be very
 conservative about the specified tape size, specially if there are filesystems
 that contain mostly uncompressible data.
 You might want to run amtapetype to determine if you have hardware-compression
 enabled for your tape-drive.
 How can I configure Amanda so that it performs full backups on the week-end
 and incrementals on weekdays?
 You can't. Amanda doesn't work this way. You just have to tell Amanda how many
 tapes you have (tapecycle), and how often you want it to perform full backups
 of each filesystem (dumpcycle). If you don't run it once a daily (including
 Saturdays and Sundays :-), you'll also want to tell Amanda how many times
 you'll run it per dumpcycle (runspercycle). It will spread full backups along
 the dumpcycle, so you won't have any full-only or incremental-only runs.
 Please also refer to "the friday-tape-question" in Collection_of_the_top_ten
 Amanda_questions._And_answers..
 What if my tape unit uses expensive tapes, and I don't want to use one tape
 per day? Can't Amanda append to tapes?
 It can't, and this is good. Tape drives and OS drivers are (in)famous for
 rewinding tapes at unexpected times, without telling the program that's
 writing to them. If you have a month's worth of backups in that tape, you
 really don't want them to be overwritten, so Amanda has taken the safe
 approach of requiring tapes to be written from the beginning on every run.
 This can be wasteful, specially if you have a small amount of data to back up,
 but expensive large-capacity tapes. One possible approach is to run amdump
 with tapes only, say once a week, to perform full backups, and run it without
 tape on the other days, so that it performs incremental backups and stores
 them in the holding disk. Once or twice a week, you flush all backups in the
 holding disk to a single tape.
 If you don't trust your holding disk, and you'd rather have all your data on
 tapes daily, you can create an alternate configuration, with two tapes, that
 backs up the holding disk only, always as a full backup. You'd run this
 configuration always after your regular backup, so you always have a complete
 image of the holding disk on tape, just in case it fails.
 How can I configure Amanda for long-term archiving?
 The best approach is to create a separate configuration for your archive
 backups. It should use a separate set of tapes, and have all dumptypes
 configured with `record no', so it doesn't interfere with regular backups.
 Can I backup separate disks of the same host in different configurations?
 Yes, but you have to be careful. Amanda uses UDP to issue estimate and backup
 requests and, although replies to backup requests are immediate (so that TCP
 connections for the actual backup can be established), replies to estimate
 requests are not and, while one request is being processed, any other request
 is ignored. The effect is two-fold:

   i. If another configuration requests for estimates, the request will be
      ignored, and the requester will end up timing out;
  ii. If another configuration has already finished the estimates, and is now
      requesting for backups, the backup requests will time-out.

 So, there are two easy ways out:

   i. Ensure that the configurations never run concurrently, or
  ii. set up two different installations of the Amanda server, using different
      services names to contact the clients, i.e., different port numbers. This
      can be attained with the configure flag --with-testing=<service-suffix>.
      Yes, the flag name is not appropriate, but so what?

 If you don't want to set up two installations of Amanda (I agree, it's
 overkill), but you still want to back up disks of the same host in separate
 configurations, you can set up Amanda so that one configuration only starts
 after the first one has already finished its One possible way to work-around
 this limitation is to start one configuration only after you know the
 estimates for the first one have already finished (modifying the crontab
 entries, according to history data). You'll also have to delay the starttime
 (a dumptype option) of the disks in the first configuration, so that they
 don't start backing up before the estimates of the second configuration
 finish.
 Can Amanda span large filesystems across multiple tapes?
 Not yet :-(
 This is an open project, looking for developers. If you'd like to help, please
 take a look at the Amanda Ongoing Projects Page (http://www.amanda.org/
 ongoing.php), where more up-to-date information is likely to be found about
 this project.
 Update September 2004: Refer to the archive of the amanda-hackers mailinglist
 (http://marc.theaimsgroup.com/?l=amanda-hackers). A patch by John Stange is
 being discussed there, which allows splitting and spanning.
 The current work-around is to use GNU tar to back up subdirectories of the
 huge filesystem separately. But be aware of the problems listed in the
 question about "results missing".
 What's the difference between option "skip-full" and "strategy nofull"?
 "strategy nofull" is supposed to handle the following situation: you run a
 full dump off-line once a millenium :-), because that disk isn't supposed to
 change at all and, if it does, changes are minimal. Amanda will run only level
 1 backups of that filesystem, to avoid the risk of overwriting a level 1
 backup needed to do a restore. Remember, you run full dumps once a millenium,
 and your tape cycle probably won't last that long :-)
 "skip-full", OTOH, is supposed to let the user run full dumps off-line
 regularly (i.e., as often as specified in the dumpcycle), while Amanda takes
 care of the incrementals. Currently, Amanda will tell you when you're supposed
 to run the level 0 backups but, if you fail to do so, Amanda will not only
 skip a full day's worth of valuable backups of the filesystem, on the day it
 told you to the full backup manually, but it will also run a level 1 backup on
 the next day, even if you have not performed the full backup yet. Worse yet:
 it might perform a level 2 on the next day, just after you have run the level
 0, so, if the disk should crash, you'd have to restore a level 0 then a level
 2, but not the level 1! Not a real problem, but definitely strange, eh?
 Why does amdump report "results missing"?
 One of the possible reasons is that you have requested too many backups of the
 host. In this case, the estimate request or the reply may not fit in a UDP
 packet. This will cause Amanda not to perform some of the backups. Fixing this
 problem involves modifying the way estimate requests are issued, so that no
 packet exceeds the maximum packet size, and issuing additional requests that
 did not fit in a UDP packet after a reply for the previous set is obtained.
 The probability of getting this problem has been considerably reduced since we
 increased the maximum UDP packet size from 1Kb to 64Kb, but some operating
 systems may not support such large packets.
 One possible work-around is to try to shorten the pathnames of the directories
 and the exclude file names, so that more requests fit in the UDP packet. You
 may create short-named links in some directory closer to the root (/) so as to
 reduce the length of names. I.e., instead of backing up /usr/home/foo and /
 usr/home/bar, create the following links:

   /.foo -> /usr/home/foo
   /.bar -> /usr/home/bar

 then list /.foo and /.bar in the disklist.
 Another approach is to group sub-directories in backup sets, instead of
 backing up them all separately. For example, create /usr/home/.bkp1 and move
 `foo' and `bar' into it, then create links so that the original pathnames
 remain functional. Then, list /usr/home/.bkp1 in the disklist. You may create
 as many `.bkp<N>' directories as you need.
 A simpler approach, that may work for you, is to backup only a subset of the
 subdirectories of a filesystem separately. The others can be backed up
 together with the root of the filesystem, using an exclude list that prevents
 duplicate backups.
 Why does amdump report "disk offline"?
 Well, assuming the disk is not really off line :-), it may be a permission
 problem, but then, amcheck would have reported it.
 Another possible reason for this failure is a filesystem error, that causes
 DUMP to crash before it estimates the backup size; a fsck may help.
 Yet another possibility is that the filesystem is so large that the backup
 program is incorrectly reporting the estimated size, for example, by printing
 a negative value that Amanda will not accept as a valid estimate. If you are
 using dump, contact your vendor and request a patch for dump that fixes this
 bug. If you are using GNU-tar, make sure it is release 1.12 or newer; 1.11.8
 won't do! Even release 1.12 may require a patch to correctly report estimates
 and dump sizes, as well as to handle sparse files correctly and quickly
 instead of printing error messages like `Read error at byte 0, reading 512
 bytes, in file ./var/log/lastlog: Bad file number' in sendsize.debug and being
 very slow. Check the patches directory of the Amanda distribution.
 What if amdump reports "dumps way too big, must skip incremental dumps"?
 It means Amanda couldn't back up some disk because it wouldn't fit in the tape
 (s) you have configured Amanda to use. It considered performing some
 incrementals instead of full dumps, so that all disks would fit, but this
 wouldn't be enough, so the disk really had to be dropped in this run.
 In general, you can just ignore this message if it happens only once in a
 while. Low-priority disks are discarded first, so you'll hardly miss really
 important data.
 One real work-around is to configure Amanda to use more tapes: increase
 `runtapes' in amanda.conf. Even if you don't have a real tape changer, you can
 act yourself as a changer (`chg-manual'; more details in the question about
 tape changer configuration), or use `chg-multi' with a single tape unit, and
 lie to Amanda that it will have two tapes to use. If you have a holding disk
 as large as a tape, and configure Amanda (2.4.1b1 or newer) not to reserve any
 space for degraded dumps, dumps that would be stored in the second tape of a
 run will be performed to the holding disk, so you can flush them to tape in
 the morning.
 amdump reported "infofile update failed". What should I do?
 Make sure all directories and files are readable and writable by the Amanda
 user, within the directory you specified as `infofile' in amanda.conf. From
 then on, only run amanda server commands ( amadmin, amdump, amflush,
 amcleanup) as the Amanda user, not as root.
 Why does Amanda sometimes promote full dumps?
 To spread the full dumps along the dumpcycle, so that daily runs take roughly
 the same amount of tape and time. As soon as you start using Amanda, it will
 run full dumps of all filesystems. Then, on the following runs, it will
 promote some backups, so as to adjust the balance. After one or two
 dumpcycles, it should stop promoting dumps. You can see how well it is doing
 with amadmin <conf> balance. If you find the results surprising, you may want
 to adjust dumpcycle or runspercycle.
 Why does amrecover report "no index records" or "disk not found"?
 The most common cause of this problem is not having enabled index generation
 in amanda.conf. The `index yes' option must be present in every dumptype for
 whose disks indexes should be generated.
 Another possibility is that amrecover is not selecting the configuration name
 that contains the backups for the selected disk. You may specify a
 configuration name with the `-C' switch, when you invoke amrecover. The
 default configuration name can only be specified at Amanda configure time
 (configure --with-config=<name>).
 Indexes are currently generated at backup-time only, so, if a backup was
 performed without creating an index, you won't be able to use amrecover to
 restore it, you'll have to use amrestore.
 Ok, I'm done with testing Amanda, now I want to put it in production. How can
 I reset its databases so as to start from scratch?
 First, remove the `curinfo' database. By default, it is a directory, but, if
 you have selected any other database format (don't, they're deprecated), they
 may be files with extensions such as .dir and .pag.
 Then, remove any log files from the log directory: log.<TIMESTAMP>.<count> and
 amdump.<count>. Finally, remove the tapelist file, stored in the directory
 that contains amanda.conf, unless amanda.conf specifies otherwise. Depending
 on the tape changer you have selected, you may also want to reset its state
 file.
 The man-page of dump says that active filesystems may be backed up
 inconsistently. What does Amanda do to prevent inconsistent backups?
 Nothing. When you back up an active filesystem, there are two possibilities:
 dump may print strange error messages about invalid blocks, then fail; in this
 case, Amanda will retry the backup on the next run.
 Files that are modified while dump runs may be backed up inconsistently. But
 then, they will be included in the next incremental backup, which should
 usually be enough.
 Large, critical files such as databases should be locked somehow, to avoid
 inconsistent backups, but there's no direct support for that in Amanda. The
 best bet is to configure Amanda to use a wrapper to dump, that locks and
 unlocks the database when appropriate.
 Which version of GNU-tar should I use?
 (This answer was slightly adapted from a posting by Paul Bijnens
 <paul.bijnens@xplanation.com>, Mon, 11 Apr 2005):

 * 1.13.19 is good.
   However it still sets return code 2 for some infrequent conditions even with
   --ignore-failed-read option. This results in Amanda thinking the total
   archive is bad, and drops the complete archive. Those conditions are very
   rare on a quiet filesystem.
 * 1.13.25 is good: no problems found (yet).
 * 1.13.9x is not good.
   It has changed the format of "tar -t", resulting in amrecover not able to
   use the indexes.
 * 1.14.x is not good.
   It writes good archives, but when restoring, it has trouble with sparse
   files; the sparse file itself, and *all* files after it cannot be read
   anymore. But you can read the archive with a good tar version (i.e. the tar
   images produced are fine).
 * 1.15.1 is good: no problems found (yet).
   Paul Bijnens: "I'm using this version on most of my clients since january
   this year (2005), and have already done successful restore too."

 What does "bumping" mean?
 The term "bumping" is used to describe the change from one backup-level to the
 next higher level. If Amanda changes from Level 0 to Level 1 for a specific
 DLE, it "bumps".
 The basic goal of "bumping" is to save precious space on the backup media as
 higher level incremental backups are smaller in size than lower level
 incremental backups.
 The disadvantage of increasing backup levels is the fact that restoring from
 higher level incremental backups needs more tapes. This increases the amount
 of work time that are needed to fully restore a DLE as well as the possibility
 of tape-errors and similar problems during the process of restore. So in
 general it is recommended to keep the levels as low as possible with the given
 hardware and data.
 There are various amanda.conf parameters to control and fine-tune Amanda's
 behavior when it comes to "bumping":
 Please refer to the amanda-manpage and the example amanda.conf for details on
 the parameters bumppercent, bumpsize, bumpdays and bumpmult.
 How do I backup a Windows server?
 Amanda is able to use smbclient to dump SMB/CIFS-shares. Refer to the Backup
 PC_hosts_using_Samba for details.
 How do I tell my iptables-based firewall to allow Amanda through?
 posted by Matt Hyclak <hyclak@math.ohiou.edu>:
 Use something like

        iptables -A INPUT -p udp -s $AMANDA_SERVER -d $AMANDA_CLIENT --dport
   10080 -j ACCEPT

 and load the ip_conntrack_amanda kernel module. I use the following in /etc/
 modprobe.conf:

        options ip_conntrack_amanda master_timeout=2400
        install ip_tables /sbin/modprobe --ignore-install ip_tables && /sbin/
   modprobe ip_conntrack_amanda

 This sets the UDP timeout for Amanda packets to 2400 seconds, up from the
 default 300 (don't hold me to that, it might be 600). I was getting estimate
 timeouts since they were taking longer than 300/600 seconds and the firewall
 would close the port.
 Makes things a little more secure than opening up everything > 1024 ;-)
 How do I get rid of pressing "q" to get rid of a pager prompt when using
 amrecover?
 compiled from postings by Paul Bijnens <paul.bijnens@xplanation.com> and Jon
 LaBadie <jon@jgcomp.com>
 Paul Bijnens wrote:
 If you have to press "q" all the time in amrecover this is related to the
 pager-binary you use. If you use Linux this will be most likely less. To teach
 less to quit when hitting EOF, you need to set something like LESS=--QUIT-AT-
 EOF; export LESS, for example in your .profile. Refer to the manpage of less
 for details.
 Jon LaBadie wrote:
 If you don't like the quit at EOF behavior "except" when in amrecover create
 an alias or a wrapper; something like:
 alias amrecov='LESS="$LESS -E" _pathto_your_amrecover'
 Is there a way to tell the pager that my terminal has "y" lines?
 Jon LaBadie <jon@jgcomp.com> wrote:
 The pager normally does it's best to find out how many lines your terminal
 has, given the right TERM-variable. Even terminals with elastic boundaries
 (e.g. xterms) work. But I have to admit that on Solaris the settings are not
 always correct. You can fix it quickly by setting an environment variable to
 e.g. LINES=24 (and export it).


Note

Refer to http://www.amanda.org/docs/faq.html for the current version of this
document.
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