1AMANDA-CHANGERS(7) Miscellanea AMANDA-CHANGERS(7)
2
6 amanda-changers - Configuring and Using Amanda Changers
7
9 Amanda uses changers to arbitrate access to devices (amanda-devices(7))
10 and data volumes. Changers provide an abstraction of tape robots, but
11 are used to manage non-tape media, too. Amanda communicates with
12 changers through the Changer API. This manpage contains a user-level
13 overview of the API, and does not address details that are only of
14 concern to developers. For that purpose, consult the Amanda source code
15 and http://wiki.zmanda.com.
16
18 The Amanda Changer API is in transition from version 1.0 - driven by
19 shell scripts invoked for each changer operation - to version 2.0,
20 composed of perl objects that can manage parallel access to multiple
21 devices and other complexity. At this point, all Amanda programs use
22 the new Changer API directly, although 1.0 changer scripts are still
23 fully supported via chg-compat.
24 The Changer API strives to treat all changers identically, so that
26 Amanda's behavior is independent of the changer in use. However, some
27 parts of Amanda operate differently depending on whether a changer can
28 efficiently search for a volume with a given label. This distinction is
29 really only apparent with tape libraries: those with barcode readers
30 can quickly find a desired tape, while those without may fall back to
31 an inefficient scan of each volume. The capability to perform quick
32 searches is called "fast-search", and each changer is annotated below
33 to indicate its support.
34
36 Changer specifications are strings like chg-disk:/my/vtapes. The chg-
37 prefix serves to differentiate changers from devices (see amanda-
38 devices(7)). The next portion (disk, in this case) identifies the
39 particular changer driver to use, and everything that follows the : is
40 interpreted by the driver. Note that the : character is required, even
41 when nothing follows it. This is an easy way to distinguish new changer
42 specifications from old.
43 A name which does not match this pattern, but which matches an old
45 changer script (e.g., chg-zd-mtx), invokes the backward-compatibility
46 changer driver as e.g., chg-compat:chg-zd-mtx. If the name does not
47 match an old changer, then it is treated as an Amanda device, and is
48 wrapped by the single-device changer, e.g., chg-single:tape:/dev/rmt/0.
49 Changers which require additional parameters can also be described in
51 amanda.conf(5) with "changer" sections. Such a changer defininition
52 creates a changer "alias", in this case named hp-robot, which can then
53 be named where an application expects a changer - for example, the
54 target of the amvault command or in a global tpchanger parameter.
55 CONFIGURATION
57 The preferred method of specifying configuration for a changer is as a
58 "changer" section in amanda.conf(5). The tapedev parameter then
59 indicates, by name, the changer that will be used by default by most
60 Amanda programs. For example:
61 define changer hp-robot {
63 tapedev "chg-robot:/dev/sg1"
64 property "tape-device" "0=tape:/dev/nst0"
65 property append "tape-device" "1=tape:/dev/nst1"
66 device-property "BLOCK_SIZE" "512k"
67 }
68 # ...
69 tapedev "hp-robot"
70 Several changer drivers accept changer properties which control the
72 behavior of the changer. These properties must be specified in a
73 changer definition, as in the hp-robot example, above.
74 Devices, too, can take properties to control their behavior (see
76 amanda-devices(7)). Device properties can come from four places:
77 implicit device properties (from tapetype parameters), global device
78 properties (from global device-property parameters), properties in
79 device definitions, and properties in changer definitions. Properties
80 are applied in this order, with later properties taking priority.
81 There are only three implicit properties: MAX_VOLUME_USAGE is set based
83 on the tapetype length parameter, READ_BLOCK_SIZE is set if
84 readblocksize is set, and BLOCK_SIZE is set based on the blocksize
85 parameter.
86 Global device properties always apply. If the changer specifies a
88 device by alias, then device properties from the definition apply. If
89 the changer is specified by an alias, then properties from that
90 definition applied.
91
93 This section lists the changer drivers included with Amanda, and basic
94 instructions for using them. For complete How-To information, consult
95 the Amanda wiki at http://wiki.zmanda.com.
96 chg-aggregate:changer (new)
98 define changer robot0 {
99 tpchanger "chg-robot:/dev/sg0"
100 property "tape-device" "0=tape:/dev/rmt/0" "1=tape:/dev/rmt/1"
101 }
102 define changer robot1 {
103 tpchanger "chg-robot:/dev/sg1"
104 property "tape-device" "0=tape:/dev/rmt/2" "1=tape:/dev/rmt/3"
105 }
106 define changer single {
107 tpchanger "chg-single:/dev/rmt/4"
108 }
109 define changer aggregate {
110 tpchanger "chg-aggregate:{robot0,robot1,single}"
111 property "state-filename" "/etc/amanda/CONF/aggregate.state"
112 }
114 tpchanger "aggregate"
115 This changer driver allow to use two or more changers or standalone
117 drive in sequence.
118 Properties
120 LOCK-TIMEOUT
121 The time in seconds amanda wait to lock the statefile
123 (default:1000)
124 STATE_FILENAME
126 The name of the state file (default:
128 "$CONFIG_DIR/$changer_name.state".
129 chg-disk:VTAPEROOT (new)
131 tpchanger "chg-disk:/var/mnt/vtapes"
132 property "num-slot" "10"
133 property "auto-create-slot" "yes"
134 property "removable" "yes"
135 property "mount" "yes"
136 property "umount" "yes"
137 property "umount-lockfile" "/etc/amanda/conf/vtapes-lock"
138 property "umount-idle" "1"
139 This changer driver replaces the old chg-disk, supporting parallel
141 access to vtapes stored in directories named slotN in the directory
142 specified after chg-disk:. It does so by creating numbered "drives" so
143 that simultaneous processes can access distinct slots. This changer is
144 fast-search capable.
145 The current slot can be accessed using the device name file:VTAPEROOT.
147 This is useful for the amrestore(8) command line.
148 Properties
150 AUTO-CREATE-SLOT
151 If a slotN directory in the range 1 to NUM-SLOT does not already
153 exist, and this property is true, then the changer will create the
154 directory.
155 LOCK-TIMEOUT
157 The time in seconds amanda wait to lock the statefile
159 (default:1000)
160 MOUNT
162 If this property is true, the changer try to mount the removable
164 disk if nothing is mounted. The system must be configured to allow
165 the amanda user to mount it.
166 NUM-SLOT
168 The minimum number of slots in the changer, where the first slot is
170 slot1. If additional slot directories exist, they will also be
171 used.
172 REMOVABLE
174 If this property is true, then the changer will verify that the
176 changer directory (e.g., /var/mnt/vtapes) is on a different
177 filesystem from its parent directory (e.g., /var/mnt). This is
178 useful for removable disks, as it will prevent Amanda from creating
179 slot directories when the removable disk is not mounted.
180 UMOUNT
182 If this property is true, the changer try to umount the removable
184 disk when it exit. The system must be configured to allow the
185 amanda user to umount it.
186 UMOUNT-LOCKFILE
188 If UMOUNT is set, it require a lockfile outside of the mount point
190 to prevent race.
191 UMOUNT-IDLE
193 If set, the changer try to umount the removable disk when it is not
195 in use. The umount-idle value is a delay in second to wait before
196 doing the umount. A value >= 1 is required to prevent useless
197 mount/umount.
198 chg-disk (old)
200 tapedev "file:/u01/vtapes"
201 tpchanger "chg-disk"
202 changerfile "chg-disk.conf" # optional file
203 This changer script supports sequential access to vtapes stored in
205 directories named slotN in the directory specified by the tapedev
206 parameter. The configuration file parameter is:
207 LASTSLOT=number # The number of slots, default to tapecycle setting.
209 This changer is not fast-search capable.
211 chg-multi:DEVICE-LIST
213 tpchanger "chg-multi:{/dev/nst0,/dev/nst1,/dev/nst2}"
214 changerfile "chg-multi-state"
215 This script simply round-robins a number of distinct device names, as
217 specified in the tpchanger setting. It is useful when all volumes for a
218 configuration have different device names -- for example, if you have
219 many standalone drive. The changerfile must exist; it is used to save
220 the state file.
221 The child devices are specified using the same syntax as for the RAIT
223 device (see amanda-changers(7)). The range specification can be
224 especially useful here:
225 tpchanger "chg-multi:s3:mycompany-backups/tape-{001..100}"
227 This changer is not fast-search capable.
229 Properties
231 FIRST-SLOT
232 This property gives the number of the first slot. The default value
234 is "1".
235 LOCK-TIMEOUT
237 The time in seconds amanda wait to lock the statefile
239 (default:1000)
240 Special Operations
242 A number of special operations are available for chg-multi via
243 amtape(8) subcommands.
244 The reset subcommand will change the current slot to the first
246 available slot, but does not erase any stored state maintained by the
247 changer.
248 The eject subcommand will eject the volume in the given drive
250 The clean subcommand is not yet implemented.
252 The update subcommand instructs the changer to update its state
254 database. Given no arguments, the changer will scan all available
255 slots, loading each tape and reading its label. Especially for large
256 libraries, this can take a long time. If only a few slots have changed,
257 they can be listed on the command line:
258 amtape CONFIG update 1-3,9
260 In this case, the changer will only scan the stated slots. Finally, the
261 changer will not scan at all if it is given the tape label for the
262 slot:
263 amtape CONFIG update 2=DailySet-028
265 In this case, the changer updates its state to indicate that
266 DailySet-028 is in slot 2, without trying to load the tape.
267 amtape CONFIG update 1-3,9=
269 In this case, the changer marks the stated slots as an unknown state.
270 chg-multi (old)
272 tpchanger "chg-multi"
273 changerfile "chg-multi-state"
274 This script simply round-robins a number of distinct device names, as
276 specified in its configuration file. It is useful when all volumes for
277 a configuration have different device names -- for example, with S3
278 devices. The changerfile need not exist; it is used as a prefix for
279 filenames of state files.
280 The configuration file has simple lines with a parameter and its value
282 separated by a space. The # character introduces a comment. The
283 configuration parameters are:
284 multieject
286 If this is 1, use an 'mt offline' command to change to the next
287 tape, or multiple such commands for skipping several tapes at a
288 time.
289 needeject
291 This option is incompatible with 'multieject'. This should be 1 for
292 changers accessed through several virtual tape devices, when the
293 changer needs the current tape to be ejected before changing to
294 another device.
295 gravity
297 Set this to 1 if the changer/stacker is unable to loop back to the
298 first tape after unloading the last one, or if you don't want
299 amanda to go through the tape stack looking for the exact tape it
300 wants instead of using the first acceptable one.
301 slot X
303 The configuration file should list as many 'slot X' statements as
304 the number of slots supported by the changer or the number of
305 separate tape drives used.
306 This changer is not fast-search capable.
308 chg-manual
310 tpchanger "chg-manual"
311 changerfile "chg-manual.conf"
312 This script simply provides distinct device names in a round-robin
314 fashion, as specified in its configuration file. It is useful when all
315 volumes for a configuration have different device names -- for example,
316 with S3 devices. The configuration file parameters are (as listed in
317 the script):
318 resend_mail=900 # resend mail every __ seconds
320 timeout_mail=604800 # time out after this many seconds (default 7 days)
321 request="[type]" # How to request a new tape (default "tty_email")
322 request="tty" # Use the tty to ask the user to change tape.
323 # Can't be use by cron
324 request="email" # Send an email to ask the user to change tape.
325 request="tty_email" # Use the tty if it exist or send an email.
326 This changer is not fast-search capable.
328 chg-zd-mtx (old)
330 tpchanger "chg-zd-mtx"
331 changerdev "/dev/sg0" # used with 'mtx -f'
332 changerfile "chg-zd-mtx.conf"
333 tapedev "tape:/dev/nst0"
334 This script interfaces with a tape drive using the Zubkoff/Dandelion
336 version of mtx. That's the version that takes a device specifier with
337 the -f option and has subcommands like status. The configuration file
338 parameters are (as listed in the script itself):
339 firstslot=? #### First storage slot (element)
341 lastslot=? #### Last storage slot (element)
342 cleanslot=-1 #### Slot with cleaner tape -- default is "-1"
343 #### Set negative to indicate no cleaner available
344 driveslot=0 #### Drive slot number. Defaults to 0
345 #### Use the 'Data Transfer Element' you want
346 autoclean=0 #### Set to '1' or greater to enable
347 autocleancount=99 #### Number of access before a clean.
348 havereader=0 #### If you have a barcode reader, set to 1.
349 offline_before_unload=0 #### Does your robot require an
350 #### 'mt offline' before mtx unload?
351 poll_drive_ready=NN #### Time (seconds) between tests to see if
352 #### the tape drive has gone ready (default: 3).
353 max_drive_wait=NN #### Maximum time (seconds) to wait for the
354 #### tape drive to become ready (default: 120).
355 initial_poll_delay=NN #### initial delay after load before polling for
356 #### readiness
357 slotinfofile=FILENAME #### record slot information to this file, in
358 #### the line-based format "SLOT LABEL\n"
359 This changer is fast-search capable if and only if havereader is true.
361 chg-rait:{CHILD1,CHILD2,..}
363 define changer vtape {
364 tpchanger "chg-disk:/path/to/vtape"
365 }
366 define changer robot {
367 tpchanger "chg-robot:/dev/sg0"
368 tapedev "tape:/dev/nst0"
369 }
370 tpchanger "chg-rait:{vtape,robot}"
371 This changer script constructs RAIT devices out of the devices provided
373 by several "sub-changers". The sub-changers are specified using the
374 same shell-like syntax as the RAIT device (see amanda-devices(7)).
375 Chg-rait does not require that all of the child changers have the same
377 slot names: compound slot names are created by combining the slot names
378 supplied by the child changers using the same shell-like syntax. For
379 example, if the child changers return slots "top", "strange", and "3",
380 then the RAIT changer will return "{top,strange,3}". This makes it
381 possible to, for example, mirror data on tapes in slots 1-10 to tapes
382 in slots 11-20 of the same robot, using two chg-zd-mtx child changers
383 (and, naturally, two tape drives). In this arrangement, the first slot
384 would be named {1,11}.
385 As a convenience to the user, the RAIT changer will also accept
387 un-braced slot names, and supply the same name to each child changer.
388 Thus with a 4-device RAIT changer, "17" is equivalent to
389 "{17,17,17,17}".
390 Drive names are parsed in a similar fashion, for operations that take
392 drive names (clean and eject).
393 This changer is fast-search capable only if all of its child changers
395 are fast-search capable.
396 Note
398 The old chg-rait script is no longer supported nor shipped with
399 Amanda, although the old script will continue to function via
400 chg-compat, giving users time to upgrade their configuration.
401 chg-null:
403 tpchanger "chg-null:"
404 This changer always provides the device "null:". It is sometimes useful
406 in conjunction with chg-rait:.
407 chg-robot:DEVICE
409 define changer robot {
410 tpchanger "chg-robot:/dev/sg0"
411 property "tape-device" "0=tape:/dev/rmt/0" "1=tape:/dev/rmt/1"
412 property "eject-before-unload" "yes"
413 property "use-slots" "1-5,11-20"
414 }
415 tpchanger "robot"
416 This changer drives a robotic tape library using the operating system's
418 mtx command. It replaces the ancient chg-zd-mtx script. The changer
419 uses all of the information available to operate as efficiently as
420 possible. Even without a barcode reader, the changer can usually load a
421 tape immediately, without resorting to a sequential scan of many tapes.
422 It is capable of sharing state across multiple Amanda configurations,
423 avoiding conflicts and optimally tracking the contents of the library.
424 This changer does not accept a changerdev parameter, but the
426 changerfile parameter can be used to specify a filename at which it
427 should store its state. Ordinarily, this state is stored in a file
428 named after the changer device under $localstatedir/amanda, e.g.,
429 /var/amanda/chg-robot-dev-sg0. There should be a single such statefile
430 for each distinct tape library attached to the Amanda server, even if
431 multiple Amanda configurations reference that library.
432 With a barcode reader present, it is possible for chg-robot to track
434 the state of the library reliably, even recognizing tapes that are
435 removed and later re-inserted (by remembering their barcodes). Without
436 barcodes, the changer can still remember the slot in which it last saw
437 the tape with a particular label, although this information can become
438 stale if the tapes are rearranged by an operator. In any case, the
439 changer will never "hunt" for a tape by repeatedly loading slots and
440 checking labels. If the changer's state is inaccurate, use the
441 amtape(8) subcommand update.
442 This changer is fast-search capable even without a barcode reader. For
444 such libraries, it is the responsibility of the operator to update the
445 changer when tapes are added to or removed from the library.
446 There is a shell script in the contrib/ directory of Amanda's source
448 distribution which can help you convert a chg-zd-mtx configuration into
449 a chg-robot configuration. Just give it your Amanda configuration name:
450 sh contrib/convert-zd-mtx-to-robot.sh $config
452 The script can be downloaded at
453 http://github.com/zmanda/amanda/raw/master/contrib/convert-zd-mtx-to-robot.sh
454 Special Operations
456 A number of special operations are available for chg-robot via
457 amtape(8) subcommands.
458 The reset subcommand will change the current slot to the first
460 available slot, but does not erase any stored state maintained by the
461 changer.
462 The eject subcommand will unload the volume in the given drive,
464 ejecting first if the changer properties dictate. Note that, despite
465 the subcommand name, the changer attempts to avoid the state where a
466 volume has been ejected from the drive but not unloaded back to a
467 storage slot.
468 The clean subcommand is not yet implemented.
470 The update subcommand instructs the changer to update its state
472 database. Given no arguments, the changer will scan all available
473 slots, loading each tape and reading its label. Especially for large
474 libraries, this can take a long time. If only a few slots have changed,
475 they can be listed on the command line:
476 amtape CONFIG update 1-3,9
478 In this case, the changer will only scan the stated slots. Finally, the
479 changer will not scan at all if it is given the tape label for the
480 slot:
481 amtape CONFIG update 2=DailySet-028
483 In this case, the changer updates its state to indicate that
484 DailySet-028 is in slot 2, without trying to load the tape.
485 amtape CONFIG update 1-3,9=
487 In this case, the changer marks the stated slots as an unknown state.
488 Properties
490 DRIVE-CHOICE
491 This property controls the algorithm used to select a drive in
493 which to load a tape. If set to the default ("lru"), the changer
494 attempts to use the least recently used drive, resulting in a
495 round-robin behavior. The "firstavail" algorithm selects the first
496 available drive, thus preferring the first drive specified via the
497 TAPE-DEVICE property.
498 EJECT-BEFORE-UNLOAD
500 Set this boolean property to true if the library requires an
502 offline operation be performed on the tape drive before it can be
503 unloaded. If set, then mt will be invoked to perform this
504 operation. Most libraries do not require this workaround.
505 EJECT-DELAY
507 This is the time between ejecting a tape and unloading the volume
509 to a storage slot, and defaults to 0 seconds. It is only used if
510 EJECT-BEFORE-UNLOAD is true. See "Timing", below.
511 FAST-SEARCH
513 This boolean property indicates whether the changer advertises the
515 ability to find volumes without sequential scanning. The
516 traditional taperscan algorithm alters its behavior based on this
517 flag, so it is sometimes necessary to adjust it, although the
518 changer will always search for a desired tape using the most
519 efficient means available. The default value is true.
520 IGNORE-BARCODES
522 If this boolean property is true, then chg-robot will ignore any
524 barcode information that the library provides. This property is
525 probably only useful when the library returns incorrect barcodes,
526 for example due to a malfunction in the barcode reader.
527 LOAD-POLL
529 This property specifies the timing of Amanda's polling for the tape
530 drive to be ready after loading a new tape. See "Timing", below.
531 The script "polls" by trying to open the tape device repeatedly
533 until no error is encountered. The property specifies the time to
534 wait before the first poll (D), the frequency at which to poll and
535 retry on errors (P); and the time after which it should give up
536 (U). The format is
537 "D [poll P [until U]]"
539 For a simple delay with no polling, use e.g.,
540 property "load-poll" "13s"
542 To delay and then poll, use e.g.,
543 property "load-poll" "13s poll 5s"
545 and to add a maximum total time, use e.g.,
546 property "load-poll" "0s poll 5s until 2m"
548 The default value is "0s poll 3s until 2m".
549 LOCK-TIMEOUT
551 The time in seconds amanda wait to lock the statefile
553 (default:1000)
554 MTX
556 The path to the 'mtx' binary. The default value is defined at
558 compile time.
559 STATUS-INTERVAL
561 This is the minimum time between invocations of mtx status to
563 determine the state of the changer library. The default value, 2
564 seconds, avoids back-to-back status invocations but ensures that
565 the metadata is up to date. For operating systems or libraries
566 where the mtx status takes a considerable time to complete, this
567 value should be increased. See "Timing", below.
568 TAPE-DEVICE
570 This property describes the correspondance of drive numbers in the
572 library to Amanda devices, in the format DRIVE=DEVICE. The
573 property can be specified multiple times to describe multiple
574 devices. The device will usually be a tape device name starting
575 with tape:, but may also refer to a device alias (see amanda-
576 devices(7)). As a shortcut, if the tapedev parameter is specified
577 in the changer definition, then it is assumed to be the device name
578 for drive 0.
579 UNLOAD-DELAY
581 This specifies the minimum time between an unload operation any any
583 subsequent operation. The default value is 0 seconds. See
584 "Timing", below.
585 USE-SLOTS
587 This property, if specifies, enumerates the slots to which this
589 changer should limit itself. The slots are specified as a
590 comma-separated list of ranges, e.g., "1-5,11-15,19,22". The
591 property can be specified more than once, and the resulting sets
592 will be combined. The changer will refuse to load tapes not found
593 in these slots, except for import/export purposes.
594 Timing
596 Tape libraries are fickle, and in many cases will report that an
597 operation is complete when it is still in progress. Chg-robot takes
598 several timing-related properties to accomodate such behavior.
599 A typical sequence of operations performed during a load are: get
601 library status, eject a tape, unload the tape back to a storage slot,
602 load a new tape, and read the label on that tape to ensure the drive is
603 ready.
604 On most systems, the library status check is nearly instantaneous --
606 the changer library provides its cached state to the host without
607 initiating any robot motion. In order to keep its metadata up-to-date,
608 chg-robot runs this command very frequently, but this frequency can be
609 reduced (at the cost of potentially stale metadata) by setting the
610 STATUS-INTERVAL property to a larger value.
611 Some tape libraries do not integrate the eject operation (performed by
613 the embedded tape drive) with the unload operation (performed by the
614 library robot), and can actually cause physical damage by attempting to
615 remove the tape before the ejection is complete. For such changers, set
616 the EJECT-DELAY property to allow enough time for the eject to
617 complete.
618 Once a tape is unloaded, if the library needs time to "quiesce" before
620 processing another command, add that time to the UNLOAD-DELAY
621 parameter. No other operations will be performed on the library until
622 this delay has elapsed.
623 Once a tape has been loaded, chg-robot waits until the drive is ready
625 before allowing Amanda to use the volume, as described for LOAD-POLL,
626 above.
627 Each of the times specified in these properties may be given as
629 integers with the optional suffix s for seconds (the default) or m for
630 minutes.
631 chg-ndmp:HOST[:PORT]@SCSIDEV
633 tpchanger "chg-ndmp:filer.company.com@/dev/sg0"
634 property "tape-device" "0=ndmp:filer.company.com@/dev/rtape0"
635 property append "tape-device" "1=ndmp:filer.company.com@/dev/rtape1"
636 property "use-slots" "1-12"
637 property "ndmp-auth" "text"
638 property "ndmp-username" "luke"
639 property "ndmp-password" "leia"
640 This changer is very similar to chg-robot, but controls a tape changer
642 on an NDMP server instead of a local device. The HOST in the tpchanger
643 should be the hostname of the NDMP server. The PORT is optional. The
644 SCSIDEV should specify the SCSI device on the NDMP server which
645 controls the changer. The format of this parameter is
646 implementation-specific.
647 The appropriate authentication properties will be automatically set on
649 any devices created by this changer.
650 Properties
652 This changer supports all of the properties supported by chg-robot,
653 although the value of MTX is ignored. The following properties are also
654 recognized:
655 NDMP_AUTH
657 Authentication method to use to connect to the NDMP server. One of
659 "md5" (default), "text", "none" (for an empty authentication
660 attempt) or "void" (for no authentication attempt at all).
661 NDMP-PASSWORD
663 The password for the NDMP server.
665 NDMP-USERNAME
667 The username for the NDMP server.
669 VERBOSE
671 If true, enables the NDMJOB library's verbose (packet-level)
673 debugging.
674 chg-single:DEVICE
676 tpchanger "chg-single:tape:/dev/nst0"
677 This changer is for use with standalone drive, it can work with any
679 device. The device (tape:/dev/nst0) must be set in the tpchanger
680 definition.
681 The chg-single changer has no property.
683 Unmaintained Changers
685 Amanda has many other changer scripts and programs beyond those
686 described here (see the changer-src/ in the source directory), but most
687 of these scripts are unmaintained and undocumented, and will be removed
688 when the new changer API is fully implemented.
689
691 amanda(8), amanda.conf(5), amanda-devices(7)
692 The Amanda Wiki: : http://wiki.zmanda.com/
694
696 Dustin J. Mitchell <dustin@zmanda.com>
697 Zmanda, Inc. (http://www.zmanda.com)
698Amanda 3.3.3 01/10/2013 AMANDA-CHANGERS(7)