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16 XML-conversion;Updates
19 This file contains answers to some questions that are frequently asked in the
20 Amanda mailing lists, specially by new users. Please take a look at this file
21 before posting, this can save us time that could be spent improving Amanda and
23 New entries and modifications are welcome; send them to mailto://amanda-
24 users@amanda.org or mailto://amanda-hackers@amanda.org.
25 You may also want to take a look at the Amanda FAQ-O-Matic http://
26 www.amanda.org/fom-serve/cache/1.html.
29 Why_does_Amanda_fail_to_build_on_my_system?
31 Why_does_amdump_report_that_all_disks_failed?
33 Why_does_amcheck_say_"port_NNN_is_not_secure"?
35 Why_does_amcheck_claim_that_the_tape_is_"not_an_Amanda_tape"?
37 Why_does_amcheck_report_"selfcheck_request_timed_out"?
39 Why_does_amandad.debug_contain_"error_receiving_message"?
41 Why_does_amcheck_say_"access_as_<username>_not_allowed..."?
43 Why_does_amcheck_report_"ip_address_#.#.#.#"_is_not_in_the_ip_list_list_for
46 Why_does_amcheck_say_"cannot_overwrite_active_tape"?
48 Why_does_amcheck_tell_me_"DUMP_program_not_available"?
50 Which_tape_changer_configuration_should_I_use_in_amanda.conf?
52 Where_do_I_get_my_tapetype-definition_from?_Do_I_have_to_run_amtapetype?
54 Should_I_use_software_or_hardware_compression?
56 How_can_I_configure_Amanda_so_that_it_performs_full_backups_on_the_week-end
57 and_incrementals_on_weekdays?
59 What_if_my_tape_unit_uses_expensive_tapes,_and_I_don't_want_to_use_one_tape
60 per_day?_Can't_Amanda_append_to_tapes?
62 How_can_I_configure_Amanda_for_long-term_archiving?
64 Can_I_backup_separate_disks_of_the_same_host_in_different_configurations?
66 Can_Amanda_span_large_filesystems_across_multiple_tapes?
68 What's_the_difference_between_option_"skip-full"_and_"strategy_nofull"?
70 Why_does_amdump_report_"results_missing"?
72 Why_does_amdump_report_"disk_offline"?
74 What_if_amdump_reports_"dumps_way_too_big,_must_skip_incremental_dumps"?
76 amdump_reported_"infofile_update_failed"._What_should_I_do?
78 Why_does_Amanda_sometimes_promote_full_dumps?
80 Why_does_amrecover_report_"no_index_records"_or_"disk_not_found"?
82 Ok,_I'm_done_with_testing_Amanda,_now_I_want_to_put_it_in_production._How_can
83 I_reset_its_databases_so_as_to_start_from_scratch?
85 The_man-page_of_dump_says_that_active_filesystems_may_be_backed_up
86 inconsistently._What_does_Amanda_do_to_prevent_inconsistent_backups?
88 Which_version_of_GNU-tar_should_I_use?
90 What_does_"bumping"_mean?
92 How_do_I_backup_a_Windows_server?
94 How_do_I_tell_my_iptables-based_firewall_to_allow_Amanda_through?
96 How_do_I_get_rid_of_pressing_"q"_to_get_rid_of_a_pager_prompt_when_using
99 Is_there_a_way_to_tell_the_pager_that_my_terminal_has_"y"_lines?
102 Why does Amanda fail to build on my system?
103 One of the most common reasons for compile-time errors is stale information in
104 config.cache, after a build on a different platform using the same build tree.
105 In order to avoid this problem, make sure you don't ever reuse build trees
106 across platforms, or at least run make distclean before running configure on
108 Another common reason for failure, that causes link-time errors, is a problem
109 in libtool that causes it to search for symbols in already-installed amanda
110 libraries, instead of in the just-built ones. This problem is known to affect
111 SunOS 4.1.3 and FreeBSD. You can usually work around it by specifying a
112 different prefix when you configure the new version of Amanda. However, it may
113 not work if the previous version of Amanda was installed in /usr/local and gcc
114 searches this directory by default; in this case, you must either remove the
115 old libraries (which you don't want to do, right? :-) or call configure with
116 the flag --disable-libtool. In this case, Amanda won't create shared
117 libraries, so binaries will be larger, but you may worry about that later.
118 You may also want to take a look at Amanda_2.5.0_-_System-Specific
119 Installation_Notes, as well as to the Amanda Patches Page (http://
120 www.amanda.org/patches/) for other known problems. If everything fails, you
121 should read the manual, but since we don't have one yet, just post a help
122 request to the amanda-users mailing list (mailto://amanda-users@amanda.org),
123 showing the last few lines of the failed build.
124 Why does amdump report that all disks failed?
125 Probably because the Amanda clients are not properly configured. Before you
126 ever run amdump, make sure amcheck succeeds. When it does, so should amdump.
127 Make sure you run amcheck as the same user that is supposed to start amdump,
128 otherwise you may get incorrect results.
129 Why does amcheck say "port NNN is not secure"?
130 Because amcheck, as some other Amanda programs, must be installed as setuid-
131 root. Run make install as "root", or chown all Amanda setuid programs to
132 "root", then chown u+s them again, if chown drops the setuid bit.
133 Why does amcheck claim that the tape is "not an Amanda tape"?
134 Because Amanda requires you to label tapes before it uses them. Run amlabel in
135 order to label a tape.
136 If, even after labeling a tape, amcheck still complains about it, make sure
137 the regular expression specified in amanda.conf matches the label you have
138 specified, and check whether you have configured non-rewinding tape devices
139 for Amanda to use. For example, use /dev/nrst0 instead of /dev/rst0, /dev/rmt/
140 0bn instead of /dev/rmt/0b, or some other system-dependent device name that
141 contains an "n", instead of one that does not. The "n" stands for non-
143 If you have labeled any tapes using the rewiding device configuration, you'll
144 have to label them again.
145 Why does amcheck report "selfcheck request timed out"?
146 This can occur under several different situations. First, make sure this
147 problem is repeatable; if Amanda programs are NFS-auto-mounted, some clients
148 may fail to mount the Amanda binaries in time.
149 If the error is repeatable, log into the client, and check whether the
150 directory /tmp/amanda exists, and a file named amandad.debug exists in there:
151 amandad will create this file whenever it starts. If this file does not exist,
152 amandad is not starting properly, or it lacks permission to create /tmp/
153 amanda/amandad.debug.
154 In the latter case, wipe out /tmp/amanda, and amandad should create it next
155 time it runs. In the former case, check your inetd configuration. Make sure
156 you have added the Amanda services to /etc/services (or the NIS services map),
157 that /etc/inetd.conf was properly configured, and that you have signalled
158 inetd to reread this file (some systems may need rebooting). Check section 2.2
159 from in the Amanda_Installation_Notes for details. Check the inetd man-page
160 for possible differences between the standard format of /etc/inetd.conf and
161 the one in your system.
162 Pay special attention to typos in /etc/inetd.conf; error messages will
163 probably appear in /var/adm/messages or /var/log/messages if you have typed
164 the amandad program name incorrectly. Make sure the same user that you have
165 specified at configure-time (configure --with-user=<USERNAME>) is listed in /
166 etc/inetd.conf. Check whether this user has permission to run amandad, as well
167 as any shared libraries amandad depends upon, by running the specified amandad
168 command by hand, as the Amanda user. It should just time-out after 30 seconds
169 waiting for a UDP packet. If you type anything, it will abort immediately,
170 because it can't read a UDP packet from the keyboard.
171 As soon as you have properly configured /etc/inetd.conf so as to run amandad,
172 you should no longer get the "selfcheck request timed out" message. A nice
173 tool to help make sure inetd is really listening on the amandad port is lsof,
174 available at ftp://vic.cc.purdue.edu/pub/tools/unix/lsof.
175 Why does amandad.debug contain "error receiving message"?
176 One possibility is that you have run amandad from the command line prompt and
177 typed anything instead of waiting for it to time-out: in this case, it will
178 try to read a UDP packet from the keyboard, and this was reported not to work
179 on most keyboards :-). However, if you have run amandad as any user other than
180 the one listed in /etc/inetd.conf, it may have created a /tmp/amanda directory
181 that the Amanda user cannot write to, so you should wipe it out.
182 Another possibility is that the Amanda service was not properly configured as
183 a UDP service; check /etc/services and /etc/inetd.conf.
184 Why does amcheck say "access as <username> not allowed..."?
185 There must be something wrong with .amandahosts configuration (or .rhosts, if
186 you have configured --without-amandahosts).
187 First, if the <username> is not what you expect (i.e., not what you have
188 specified in the --with-user flag, at configure time), check the inetd
189 configuration file: you must have specified the wrong username there.
190 Make sure you specify the names exactly as they appear in the error message
191 after the `@' sign in .amandahosts/.rhosts. You'll need a fully-qualified
192 domain name or not, depending on how your client resolves IP addresses to host
194 Why does amcheck report "ip address #.#.#.#" is not in the ip list list for
196 Check your DNS configuration tables. In order to avoid DNS-spoofing, Amanda
197 double-checks hostname<->IP address mapping. If the IP address the request
198 comes from maps to a hostname, but this hostname does not map back to the
199 incoming IP address, the request is denied.
200 Why does amcheck say "cannot overwrite active tape"?
201 Because, if you configure Amanda to use N tapes, by setting tapecycle to N in
202 amanda.conf, before Amanda overwrites a tape, it must write to at least other
203 N-1 tapes. Of course, Amanda will always refuse to overwrite a tape marked for
204 `noreuse' with amadmin. Furthermore, such tapes are not counted when Amanda
205 computes `N-1' tapes.
206 If, for some reason, you want to tell Amanda to overwrite a particular tape,
207 regardless of its position in the cycle, use amrmtape. This command will
208 remove this tape from the tapelist file, that is used to manage the tape
209 cycle, and will delete information about backups stored in that tape from the
211 Why does amcheck tell me "DUMP program not available"?
212 Because configure could not find dump when it was first run. This is a common
213 problem on Linux hosts, because most Linux distributions do not install dump
215 If you don't have a DUMP program installed, install it, remove config.cache,
216 run configure again and rebuild Amanda. While configure is running, make sure
217 it can find the installed DUMP program. If it cannot, you may have to set the
218 environment variables DUMP and RESTORE by hand, before running configure.
219 If you can't or don't want to install DUMP, you may use GNU tar, but make sure
220 it as release 1.12 or newer; release 1.11.8 may work, but estimates will be
222 Which tape changer configuration should I use in amanda.conf?
223 If you only have one tape unit, you have two choices:
225 i. Don't use a tape changer at all, i.e., set runtapes to 1, set tapedev to
226 the non-rewinding device corresponding to the tape unit, and comment out
227 tpchanger, changerfile and changerdev
228 ii. Set up chg-manual, so that you can change tapes manually. If you select
229 chg-manual, you will not be able to start amdump as a cron job, and you
230 should always run amflush -f, because chg-manual will ask you to press
231 return in the terminal where you started the controlling program.
233 If you have several tape units, which you want to use to emulate a tape
234 changer, you want chg-multi. Even if you do own a real tape changer, that
235 operates based on ejecting a tape or such, chg-multi may be useful.
236 Actual tape changers usually require specialized changer programs, such as
237 mtx, chio or specific system calls. The availability of these programs is much
238 more dependent on the operating system you're running than on the particular
239 tape changer hardware you have.
240 mtx, for example, is available for several platforms. However, even if you
241 find it for your platform, beware that there exist several different programs
242 named mtx, that require different command line arguments, and print different
243 output, and Amanda's chg-mtx does not support them all. You may have to edit
244 the script, which shouldn't be hard to do.
245 In section BUILT-IN TAPE CHANGERS of Amanda_Tape_Changer_Support you will find
246 details about the tape changer interfacing programs provided with Amanda, that
247 can interact with common tape changer programs and with tape changer-related
248 system calls provided by some operating system. If none of them matches your
249 needs, you may have to develop your own tape changer interface script.
250 Before posting a question to the Amanda mailing lists, *please* search the
251 archives, and try to obtain as much information about driving your tape
252 changer hardware from the vendor of the changer hardware and of the operating
253 system, rather than from the Amanda mailing lists. We usually don't have much
254 to say about tape changer units, and several questions about them remain
256 Anyway, if you decide to post a question, make sure you specify both the tape
257 changer hardware *and* the OS/platform that is going to interface with it.
259 Where do I get my tapetype-definition from? Do I have to run amtapetype?
260 It is not mandatory to run amtapetype at installation-time. It is very likely
261 that your tapedrive or -changer is one of the devices that are already covered
262 by one of the existing tapetype-definitions.
263 You may find tapetype-definitions in the example amanda.conf, in the
264 mailinglist-archives of the amanda-users-mailinglist at http://
265 marc.theaimsgroup.com/?l=amanda-users or in the Amanda-FAQ-O-Matic at http://
266 www.amanda.org/fom-serve/cache/1.html.
267 Reasons to run amtapetype for your device:
269 * You want to generate your own tapetype-definition because you can't find any
270 suitable tapetype-definition for your device.
271 * You want to determine the performance of your device.
272 * You want to determine if your device has hardware-compression enabled.
274 If you decide to run amtapetype, please refer to the chapter Tapetypes and the
275 manpage amtapetype(8).
276 Should I use software or hardware compression?
277 When you enable software compression, you drastically reduce the compression
278 that might be achieved by hardware. In fact, tape drives will usually use
279 *more* tape if you tell them to try to further compress already compressed
281 Thus, you must choose whether you're going to use software or hardware
282 compression; don't ever enable both unless you want to waste tape space.
283 Since Amanda prefers to have complete information about tape sizes and
284 compression rates, it can do a better job if you use software compression.
285 However, if you can't afford the extra CPU usage, Amanda can live with the
286 unpredictability of hardware compression, but you'll have to be very
287 conservative about the specified tape size, specially if there are filesystems
288 that contain mostly uncompressible data.
289 You might want to run amtapetype to determine if you have hardware-compression
290 enabled for your tape-drive.
291 How can I configure Amanda so that it performs full backups on the week-end
292 and incrementals on weekdays?
293 You can't. Amanda doesn't work this way. You just have to tell Amanda how many
294 tapes you have (tapecycle), and how often you want it to perform full backups
295 of each filesystem (dumpcycle). If you don't run it once a daily (including
296 Saturdays and Sundays :-), you'll also want to tell Amanda how many times
297 you'll run it per dumpcycle (runspercycle). It will spread full backups along
298 the dumpcycle, so you won't have any full-only or incremental-only runs.
299 Please also refer to "the friday-tape-question" in Collection_of_the_top_ten
300 Amanda_questions._And_answers..
301 What if my tape unit uses expensive tapes, and I don't want to use one tape
302 per day? Can't Amanda append to tapes?
303 It can't, and this is good. Tape drives and OS drivers are (in)famous for
304 rewinding tapes at unexpected times, without telling the program that's
305 writing to them. If you have a month's worth of backups in that tape, you
306 really don't want them to be overwritten, so Amanda has taken the safe
307 approach of requiring tapes to be written from the beginning on every run.
308 This can be wasteful, specially if you have a small amount of data to back up,
309 but expensive large-capacity tapes. One possible approach is to run amdump
310 with tapes only, say once a week, to perform full backups, and run it without
311 tape on the other days, so that it performs incremental backups and stores
312 them in the holding disk. Once or twice a week, you flush all backups in the
313 holding disk to a single tape.
314 If you don't trust your holding disk, and you'd rather have all your data on
315 tapes daily, you can create an alternate configuration, with two tapes, that
316 backs up the holding disk only, always as a full backup. You'd run this
317 configuration always after your regular backup, so you always have a complete
318 image of the holding disk on tape, just in case it fails.
319 How can I configure Amanda for long-term archiving?
320 The best approach is to create a separate configuration for your archive
321 backups. It should use a separate set of tapes, and have all dumptypes
322 configured with `record no', so it doesn't interfere with regular backups.
323 Can I backup separate disks of the same host in different configurations?
324 Yes, but you have to be careful. Amanda uses UDP to issue estimate and backup
325 requests and, although replies to backup requests are immediate (so that TCP
326 connections for the actual backup can be established), replies to estimate
327 requests are not and, while one request is being processed, any other request
328 is ignored. The effect is two-fold:
330 i. If another configuration requests for estimates, the request will be
331 ignored, and the requester will end up timing out;
332 ii. If another configuration has already finished the estimates, and is now
333 requesting for backups, the backup requests will time-out.
335 So, there are two easy ways out:
337 i. Ensure that the configurations never run concurrently, or
338 ii. set up two different installations of the Amanda server, using different
339 services names to contact the clients, i.e., different port numbers. This
340 can be attained with the configure flag --with-testing=<service-suffix>.
341 Yes, the flag name is not appropriate, but so what?
343 If you don't want to set up two installations of Amanda (I agree, it's
344 overkill), but you still want to back up disks of the same host in separate
345 configurations, you can set up Amanda so that one configuration only starts
346 after the first one has already finished its One possible way to work-around
347 this limitation is to start one configuration only after you know the
348 estimates for the first one have already finished (modifying the crontab
349 entries, according to history data). You'll also have to delay the starttime
350 (a dumptype option) of the disks in the first configuration, so that they
351 don't start backing up before the estimates of the second configuration
353 Can Amanda span large filesystems across multiple tapes?
355 This is an open project, looking for developers. If you'd like to help, please
356 take a look at the Amanda Ongoing Projects Page (http://www.amanda.org/
357 ongoing.php), where more up-to-date information is likely to be found about
359 Update September 2004: Refer to the archive of the amanda-hackers mailinglist
360 (http://marc.theaimsgroup.com/?l=amanda-hackers). A patch by John Stange is
361 being discussed there, which allows splitting and spanning.
362 The current work-around is to use GNU tar to back up subdirectories of the
363 huge filesystem separately. But be aware of the problems listed in the
364 question about "results missing".
365 What's the difference between option "skip-full" and "strategy nofull"?
366 "strategy nofull" is supposed to handle the following situation: you run a
367 full dump off-line once a millenium :-), because that disk isn't supposed to
368 change at all and, if it does, changes are minimal. Amanda will run only level
369 1 backups of that filesystem, to avoid the risk of overwriting a level 1
370 backup needed to do a restore. Remember, you run full dumps once a millenium,
371 and your tape cycle probably won't last that long :-)
372 "skip-full", OTOH, is supposed to let the user run full dumps off-line
373 regularly (i.e., as often as specified in the dumpcycle), while Amanda takes
374 care of the incrementals. Currently, Amanda will tell you when you're supposed
375 to run the level 0 backups but, if you fail to do so, Amanda will not only
376 skip a full day's worth of valuable backups of the filesystem, on the day it
377 told you to the full backup manually, but it will also run a level 1 backup on
378 the next day, even if you have not performed the full backup yet. Worse yet:
379 it might perform a level 2 on the next day, just after you have run the level
380 0, so, if the disk should crash, you'd have to restore a level 0 then a level
381 2, but not the level 1! Not a real problem, but definitely strange, eh?
382 Why does amdump report "results missing"?
383 One of the possible reasons is that you have requested too many backups of the
384 host. In this case, the estimate request or the reply may not fit in a UDP
385 packet. This will cause Amanda not to perform some of the backups. Fixing this
386 problem involves modifying the way estimate requests are issued, so that no
387 packet exceeds the maximum packet size, and issuing additional requests that
388 did not fit in a UDP packet after a reply for the previous set is obtained.
389 The probability of getting this problem has been considerably reduced since we
390 increased the maximum UDP packet size from 1Kb to 64Kb, but some operating
391 systems may not support such large packets.
392 One possible work-around is to try to shorten the pathnames of the directories
393 and the exclude file names, so that more requests fit in the UDP packet. You
394 may create short-named links in some directory closer to the root (/) so as to
395 reduce the length of names. I.e., instead of backing up /usr/home/foo and /
396 usr/home/bar, create the following links:
398 /.foo -> /usr/home/foo
399 /.bar -> /usr/home/bar
401 then list /.foo and /.bar in the disklist.
402 Another approach is to group sub-directories in backup sets, instead of
403 backing up them all separately. For example, create /usr/home/.bkp1 and move
404 `foo' and `bar' into it, then create links so that the original pathnames
405 remain functional. Then, list /usr/home/.bkp1 in the disklist. You may create
406 as many `.bkp<N>' directories as you need.
407 A simpler approach, that may work for you, is to backup only a subset of the
408 subdirectories of a filesystem separately. The others can be backed up
409 together with the root of the filesystem, using an exclude list that prevents
411 Why does amdump report "disk offline"?
412 Well, assuming the disk is not really off line :-), it may be a permission
413 problem, but then, amcheck would have reported it.
414 Another possible reason for this failure is a filesystem error, that causes
415 DUMP to crash before it estimates the backup size; a fsck may help.
416 Yet another possibility is that the filesystem is so large that the backup
417 program is incorrectly reporting the estimated size, for example, by printing
418 a negative value that Amanda will not accept as a valid estimate. If you are
419 using dump, contact your vendor and request a patch for dump that fixes this
420 bug. If you are using GNU-tar, make sure it is release 1.12 or newer; 1.11.8
421 won't do! Even release 1.12 may require a patch to correctly report estimates
422 and dump sizes, as well as to handle sparse files correctly and quickly
423 instead of printing error messages like `Read error at byte 0, reading 512
424 bytes, in file ./var/log/lastlog: Bad file number' in sendsize.debug and being
425 very slow. Check the patches directory of the Amanda distribution.
426 What if amdump reports "dumps way too big, must skip incremental dumps"?
427 It means Amanda couldn't back up some disk because it wouldn't fit in the tape
428 (s) you have configured Amanda to use. It considered performing some
429 incrementals instead of full dumps, so that all disks would fit, but this
430 wouldn't be enough, so the disk really had to be dropped in this run.
431 In general, you can just ignore this message if it happens only once in a
432 while. Low-priority disks are discarded first, so you'll hardly miss really
434 One real work-around is to configure Amanda to use more tapes: increase
435 `runtapes' in amanda.conf. Even if you don't have a real tape changer, you can
436 act yourself as a changer (`chg-manual'; more details in the question about
437 tape changer configuration), or use `chg-multi' with a single tape unit, and
438 lie to Amanda that it will have two tapes to use. If you have a holding disk
439 as large as a tape, and configure Amanda (2.4.1b1 or newer) not to reserve any
440 space for degraded dumps, dumps that would be stored in the second tape of a
441 run will be performed to the holding disk, so you can flush them to tape in
443 amdump reported "infofile update failed". What should I do?
444 Make sure all directories and files are readable and writable by the Amanda
445 user, within the directory you specified as `infofile' in amanda.conf. From
446 then on, only run amanda server commands ( amadmin, amdump, amflush,
447 amcleanup) as the Amanda user, not as root.
448 Why does Amanda sometimes promote full dumps?
449 To spread the full dumps along the dumpcycle, so that daily runs take roughly
450 the same amount of tape and time. As soon as you start using Amanda, it will
451 run full dumps of all filesystems. Then, on the following runs, it will
452 promote some backups, so as to adjust the balance. After one or two
453 dumpcycles, it should stop promoting dumps. You can see how well it is doing
454 with amadmin <conf> balance. If you find the results surprising, you may want
455 to adjust dumpcycle or runspercycle.
456 Why does amrecover report "no index records" or "disk not found"?
457 The most common cause of this problem is not having enabled index generation
458 in amanda.conf. The `index yes' option must be present in every dumptype for
459 whose disks indexes should be generated.
460 Another possibility is that amrecover is not selecting the configuration name
461 that contains the backups for the selected disk. You may specify a
462 configuration name with the `-C' switch, when you invoke amrecover. The
463 default configuration name can only be specified at Amanda configure time
464 (configure --with-config=<name>).
465 Indexes are currently generated at backup-time only, so, if a backup was
466 performed without creating an index, you won't be able to use amrecover to
467 restore it, you'll have to use amrestore.
468 Ok, I'm done with testing Amanda, now I want to put it in production. How can
469 I reset its databases so as to start from scratch?
470 First, remove the `curinfo' database. By default, it is a directory, but, if
471 you have selected any other database format (don't, they're deprecated), they
472 may be files with extensions such as .dir and .pag.
473 Then, remove any log files from the log directory: log.<TIMESTAMP>.<count> and
474 amdump.<count>. Finally, remove the tapelist file, stored in the directory
475 that contains amanda.conf, unless amanda.conf specifies otherwise. Depending
476 on the tape changer you have selected, you may also want to reset its state
478 The man-page of dump says that active filesystems may be backed up
479 inconsistently. What does Amanda do to prevent inconsistent backups?
480 Nothing. When you back up an active filesystem, there are two possibilities:
481 dump may print strange error messages about invalid blocks, then fail; in this
482 case, Amanda will retry the backup on the next run.
483 Files that are modified while dump runs may be backed up inconsistently. But
484 then, they will be included in the next incremental backup, which should
486 Large, critical files such as databases should be locked somehow, to avoid
487 inconsistent backups, but there's no direct support for that in Amanda. The
488 best bet is to configure Amanda to use a wrapper to dump, that locks and
489 unlocks the database when appropriate.
490 Which version of GNU-tar should I use?
491 (This answer was slightly adapted from a posting by Paul Bijnens
492 <paul.bijnens@xplanation.com>, Mon, 11 Apr 2005):
495 However it still sets return code 2 for some infrequent conditions even with
496 --ignore-failed-read option. This results in Amanda thinking the total
497 archive is bad, and drops the complete archive. Those conditions are very
498 rare on a quiet filesystem.
499 * 1.13.25 is good: no problems found (yet).
500 * 1.13.9x is not good.
501 It has changed the format of "tar -t", resulting in amrecover not able to
503 * 1.14.x is not good.
504 It writes good archives, but when restoring, it has trouble with sparse
505 files; the sparse file itself, and *all* files after it cannot be read
506 anymore. But you can read the archive with a good tar version (i.e. the tar
507 images produced are fine).
508 * 1.15.1 is good: no problems found (yet).
509 Paul Bijnens: "I'm using this version on most of my clients since january
510 this year (2005), and have already done successful restore too."
512 What does "bumping" mean?
513 The term "bumping" is used to describe the change from one backup-level to the
514 next higher level. If Amanda changes from Level 0 to Level 1 for a specific
516 The basic goal of "bumping" is to save precious space on the backup media as
517 higher level incremental backups are smaller in size than lower level
519 The disadvantage of increasing backup levels is the fact that restoring from
520 higher level incremental backups needs more tapes. This increases the amount
521 of work time that are needed to fully restore a DLE as well as the possibility
522 of tape-errors and similar problems during the process of restore. So in
523 general it is recommended to keep the levels as low as possible with the given
525 There are various amanda.conf parameters to control and fine-tune Amanda's
526 behavior when it comes to "bumping":
527 Please refer to the amanda-manpage and the example amanda.conf for details on
528 the parameters bumppercent, bumpsize, bumpdays and bumpmult.
529 How do I backup a Windows server?
530 Amanda is able to use smbclient to dump SMB/CIFS-shares. Refer to the Backup
531 PC_hosts_using_Samba for details.
532 How do I tell my iptables-based firewall to allow Amanda through?
533 posted by Matt Hyclak <hyclak@math.ohiou.edu>:
536 iptables -A INPUT -p udp -s $AMANDA_SERVER -d $AMANDA_CLIENT --dport
539 and load the ip_conntrack_amanda kernel module. I use the following in /etc/
542 options ip_conntrack_amanda master_timeout=2400
543 install ip_tables /sbin/modprobe --ignore-install ip_tables && /sbin/
544 modprobe ip_conntrack_amanda
546 This sets the UDP timeout for Amanda packets to 2400 seconds, up from the
547 default 300 (don't hold me to that, it might be 600). I was getting estimate
548 timeouts since they were taking longer than 300/600 seconds and the firewall
549 would close the port.
550 Makes things a little more secure than opening up everything > 1024 ;-)
551 How do I get rid of pressing "q" to get rid of a pager prompt when using
553 compiled from postings by Paul Bijnens <paul.bijnens@xplanation.com> and Jon
554 LaBadie <jon@jgcomp.com>
556 If you have to press "q" all the time in amrecover this is related to the
557 pager-binary you use. If you use Linux this will be most likely less. To teach
558 less to quit when hitting EOF, you need to set something like LESS=--QUIT-AT-
559 EOF; export LESS, for example in your .profile. Refer to the manpage of less
562 If you don't like the quit at EOF behavior "except" when in amrecover create
563 an alias or a wrapper; something like:
564 alias amrecov='LESS="$LESS -E" _pathto_your_amrecover'
565 Is there a way to tell the pager that my terminal has "y" lines?
566 Jon LaBadie <jon@jgcomp.com> wrote:
567 The pager normally does it's best to find out how many lines your terminal
568 has, given the right TERM-variable. Even terminals with elastic boundaries
569 (e.g. xterms) work. But I have to admit that on Solaris the settings are not
570 always correct. You can fix it quickly by setting an environment variable to
571 e.g. LINES=24 (and export it).
576 Refer to http://www.amanda.org/docs/faq.html for the current version of this
578 -------------------------------------------------------------------------------
581 Chapter 18. Using Amanda Home Chapter 20. Collection of the top ten Amanda
582 questions. And answers.