-
- Chapter 19. Amanda FAQ
-Prev Part IV. Various Information Next
-
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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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