4 \chapter{Autochanger Support}
5 \label{_ChapterStart18}
6 \index[general]{Support!Autochanger }
7 \index[general]{Autochanger Support }
9 \section{Autochangers -- General}
10 \index[general]{General!Autochangers -- }
11 \index[general]{Autochangers -- General }
13 Bacula provides autochanger support for reading and writing tapes. In
14 order to work with an autochanger, Bacula requires a number of things, each of
15 which is explained in more detail after this list:
18 \item A script that actually controls the autochanger according to commands
19 sent by Bacula. We furnish such a script that works with {\bf mtx} found in
20 the {\bf depkgs} distribution. This script works only with single drive
22 \item That each Volume (tape) to be used must be defined in the Catalog and
23 have a Slot number assigned to it so that Bacula knows where the Volume is in
24 the autochanger. This is generally done with the {\bf label} command. See
25 below for more details. You must pre-label the tapes manually before
27 \item Modifications to your Storage daemon's Device configuration resource to
28 identify that the device is a changer, as well as a few other parameters.
29 \item You should also modify your Storage resource definition in the
30 Director's configuration file so that you are automatically prompted for the
31 Slot when labeling a Volume.
32 \item You need to ensure that your Storage daemon (if not running as root)
33 has access permissions to both the tape drive and the control device.
34 \item You need to have {\bf Autochanger = yes} in your Storage resource
35 in your bacula-dir.conf file so that you will be prompted for the
36 slot number when you label Volumes.
39 In version 1.37 and later, there is a new \ilink{Autochanger
40 resource}{AutochangerRes} that permits you to group Device resources thus
41 creating a multi-drive autochanger. If you have an autochanger,
42 you must use this new resource.
44 Bacula uses its own {\bf mtx-changer} script to interface with a program
45 that actually does the tape changing. Thus in principle, {\bf mtx-changer}
46 can be adapted to function with any autochanger program. The current
47 version of {\bf mtx-changer} works with the {\bf mtx} program. However,
48 FreeBSD users have provided a script in the {\bf examples/autochangers}
49 directory that allows Bacula to use the {\bf chio} program.
51 Bacula also supports autochangers with barcode
52 readers. This support includes two Console commands: {\bf label barcodes}
53 and {\bf update slots}. For more details on these commands, see the "Barcode
54 Support" section below.
56 Current Bacula autochanger support does not include cleaning, stackers, or
57 silos. However, under certain conditions, you may be able to make Bacula
58 work with stackers (gravity feed and such). Support for multi-drive
59 autochangers requires the \ilink{Autochanger resource}{AutochangerRes}
60 introduced in version 1.37. This resource is also recommended for single
63 In principle, if {\bf mtx} will operate your changer correctly, then it is
64 just a question of adapting the {\bf mtx-changer} script (or selecting one
65 already adapted) for proper interfacing. You can find a list of autochangers
66 supported by {\bf mtx} at the following link:
67 \elink{http://mtx.badtux.net/compatibility.php}
68 {http://mtx.badtux.net/compatibility.php}.
69 The home page for the {\bf mtx} project can be found at:
70 \elink{http://mtx.badtux.net/}{http://mtx.badtux.net/}.
72 If you are having troubles, please use the {\bf auto} command in the {\bf
73 btape} program to test the functioning of your autochanger with Bacula. When
74 Bacula is running, please remember that for many distributions (e.g. FreeBSD,
75 Debian, ...) the Storage daemon runs as {\bf bacula.tape} rather than {\bf
76 root.root}, so you will need to ensure that the Storage daemon has sufficient
77 permissions to access the autochanger.
80 \section{Knowing What SCSI Devices You Have}
81 \index[general]{Have!Knowing What SCSI Devices You }
82 \index[general]{Knowing What SCSI Devices You Have }
83 \index[general]{SCSI devices}
84 \index[general]{devices!SCSI}
94 to see what SCSI devices you have available. You can also:
98 cat /proc/scsi/sg/device_hdr /proc/scsi/sg/devices
102 to find out how to specify their control address ({\bf /dev/sg0} for the
103 first, {\bf /dev/sg1} for the second, ...) on the {\bf Changer Device = }
106 Under FreeBSD, you can use:
114 To list the SCSI devices as well as the {\bf /dev/passn} that you will use on
115 the Bacula {\bf Changer Device = } directive.
117 Please check that your Storage daemon has permission to access this
120 The following tip for FreeBSD users comes from Danny Butroyd:
121 n reboot bacula will NOT have permissions to
122 control the device /dev/pass0 (assuming this is your changer device).
123 To get around this just edit the /etc/devfs.conf file and add the
124 following to the bottom of the config file:
127 own pass0 root:bacula
129 own nsa0.0 root:bacula
133 I have given the bacula group permission to write to the nsa0.0 device
134 too just to be on the safe side. To bring these changes into effect
137 /etc/rc.d/devfs restart
139 Basically this will stop you having to change permissions on these
140 devices to make bacula work when operating the AutoChanger after a reboot.
144 \section{Example Scripts}
145 \index[general]{Scripts!Example }
146 \index[general]{Example Scripts }
148 Please read the sections below so that you understand how autochangers work
149 with Bacula. Although we supply a default {\bf mtx-changer} script, your
150 autochanger may require some additional changes. If you want to see examples
151 of configuration files and scripts, please look in the {\bf
152 \lt{}bacula-src\gt{}/examples/devices} directory where you will find an
153 example {\bf HP-autoloader.conf} Bacula Device resource, and several {\bf
154 mtx-changer} scripts that have been modified to work with different
160 \index[general]{Slots }
162 To properly address autochangers, Bacula must know which Volume is in each
163 {\bf slot} of the autochanger. Slots are where the changer cartridges reside
164 when not loaded into the drive. Bacula numbers these slots from one to the
165 number of cartridges contained in the autochanger.
167 Bacula will not automatically use a Volume in your autochanger unless it is
168 labeled and the slot number is stored in the catalog and the Volume is marked
169 as InChanger. For each Volume in your
170 changer, you will, using the Console program, assign a slot. This information
171 is kept in {\bf Bacula's} catalog database along with the other data for the
172 volume. If no slot is given, or the slot is set to zero, Bacula will not
173 attempt to use the autochanger even if all the necessary configuration records
174 are present. In addition, the console {\bf mount} command does not cause
175 Bacula to operate the autochanger, it only tells Bacula to read any tape that
178 You can check if the Slot number and InChanger flag are set by doing a:
183 in the Console program.
186 \section{Multiple Devices}
187 \index[general]{Devices!Multiple }
188 \index[general]{Multiple Devices }
190 Some autochangers have more than one read/write device (drive). The
192 \ilink{Autochanger resource}{AutochangerRes} introduced in version
193 1.37 permits you to group Device resources, where each device
194 represents a drive. The Director may still reference the Devices (drives)
195 directly, but doing so, bypasses the proper functioning of the
196 drives together. Instead, the Director (in the Storage resource)
197 should reference the Autochanger resource name. Doing so permits
198 the Storage daemon to ensure that only one drive uses the mtx-changer
199 script at a time, and also that two drives don't reference the
202 Multi-drive requires the use of the {\bf
203 Drive Index} directive in the Device resource of the Storage daemon's
204 configuration file. Drive numbers or the Device Index are numbered beginning
205 at zero, which is the default. To use the second Drive in an autochanger, you
206 need to define a second Device resource and set the Drive Index to 1 for
207 that device. In general, the second device will have the same {\bf Changer
208 Device} (control channel) as the first drive, but a different {\bf Archive
211 \label{ConfigRecords}
212 \section{Device Configuration Records}
213 \index[general]{Records!Device Configuration }
214 \index[general]{Device Configuration Records }
216 Configuration of autochangers within Bacula is done in the Device resource of
217 the Storage daemon. Four records: {\bf Autochanger}, {\bf Changer Device},
218 {\bf Changer Command}, and {\bf Maximum Changer Wait} control how Bacula uses
221 These four records, permitted in {\bf Device} resources, are described in
222 detail below. Note, however, that the {\bf Changer Device} and the
223 {\bf Changer Command} directives are not needed in the Device resource
224 if they are present in the {\bf Autochanger} resource.
228 \item [Autochanger = {\it Yes|No} ]
229 \index[sd]{Autochanger }
230 The {\bf Autochanger} record specifies that the current device is or is not
231 an autochanger. The default is {\bf no}.
233 \item [Changer Device = \lt{}device-name\gt{}]
234 \index[sd]{Changer Device }
235 In addition to the Archive Device name, you must specify a {\bf Changer
236 Device} name. This is because most autochangers are controlled through a
237 different device than is used for reading and writing the cartridges. For
238 example, on Linux, one normally uses the generic SCSI interface for
239 controlling the autochanger, but the standard SCSI interface for reading and
240 writing the tapes. On Linux, for the {\bf Archive Device = /dev/nst0}, you
241 would typically have {\bf Changer Device = /dev/sg0}. Note, some of the more
242 advanced autochangers will locate the changer device on {\bf /dev/sg1}. Such
243 devices typically have several drives and a large number of tapes.
245 On FreeBSD systems, the changer device will typically be on {\bf /dev/pass0}
246 through {\bf /dev/passn}.
248 On Solaris, the changer device will typically be some file under {\bf
251 Please ensure that your Storage daemon has permission to access this
254 \item [Changer Command = \lt{}command\gt{}]
255 \index[sd]{Changer Command }
256 This record is used to specify the external program to call and what
257 arguments to pass to it. The command is assumed to be a standard program or
258 shell script that can be executed by the operating system. This command is
259 invoked each time that Bacula wishes to manipulate the autochanger. The
260 following substitutions are made in the {\bf command} before it is sent to
261 the operating system for execution:
266 %a = archive device name
267 %c = changer device name
268 %d = changer drive index base 0
271 %o = command (loaded, load, or unload)
278 An actual example for using {\bf mtx} with the {\bf mtx-changer} script (part
279 of the Bacula distribution) is:
283 Changer Command = "/etc/bacula/mtx-changer %c %o %S %a %d"
287 Where you will need to adapt the {\bf /etc/bacula} to be the actual path on
288 your system where the mtx-changer script resides. Details of the three
289 commands currently used by Bacula (loaded, load, unload) as well as the
290 output expected by Bacula are give in the {\bf Bacula Autochanger Interface}
293 \item [Maximum Changer Wait = \lt{}time\gt{}]
294 \index[sd]{Maximum Changer Wait }
295 This record is used to define the maximum amount of time that Bacula
296 will wait for an autoloader to respond to a command (e.g. load). The
297 default is set to 120 seconds. If you have a slow autoloader you may
298 want to set it longer.
300 If the autoloader program fails to respond in this time, it will be killed
301 and Bacula will request operator intervention.
303 \item [Drive Index = \lt{}number\gt{}]
304 \index[sd]{Drive Index }
305 This record allows you to tell Bacula to use the second or subsequent
306 drive in an autochanger with multiple drives. Since the drives are
307 numbered from zero, the second drive is defined by
316 To use the second drive, you need a second Device resource definition in the
317 Bacula configuration file. See the Multiple Drive section above in this
318 chapter for more information.
321 In addition, for proper functioning of the Autochanger, you must
322 define an Autochanger resource.
323 \input{autochangerres}
326 \section{An Example Configuration File}
327 \index[general]{Example Configuration File }
328 \index[general]{File!Example Configuration }
330 The following two resources implement an autochanger:
337 Changer Device = /dev/sg0
338 Changer Command = "/etc/bacula/mtx-changer %c %o %S %a %d"
344 Archive Device = /dev/nst0 # Normal archive device
347 AutomaticMount = yes;
353 where you will adapt the {\bf Archive Device}, the {\bf Changer Device}, and
354 the path to the {\bf Changer Command} to correspond to the values used on your
357 \section{A Multi-drive Example Configuration File}
358 \index[general]{Multi-drive Example Configuration File }
360 The following resources implement a multi-drive autochanger:
366 Device = Drive-1, Drive-2
367 Changer Device = /dev/sg0
368 Changer Command = "/etc/bacula/mtx-changer %c %o %S %a %d"
375 Archive Device = /dev/nst0 # Normal archive device
378 AutomaticMount = yes;
386 Archive Device = /dev/nst1 # Normal archive device
389 AutomaticMount = yes;
396 where you will adapt the {\bf Archive Device}, the {\bf Changer Device}, and
397 the path to the {\bf Changer Command} to correspond to the values used on your
400 \label{SpecifyingSlots}
401 \section{Specifying Slots When Labeling}
402 \index[general]{Specifying Slots When Labeling }
403 \index[general]{Labeling!Specifying Slots When }
405 If you add an {\bf Autochanger = yes} record to the Storage resource in your
406 Director's configuration file, the Bacula Console will automatically prompt
407 you for the slot number when the Volume is in the changer when
408 you {\bf add} or {\bf label} tapes for that Storage device. If your
409 {\bf mtx-changer} script is properly installed, Bacula will automatically
410 load the correct tape during the label command.
413 {\bf Autochanger = yes} in the Storage daemon's Device resource
414 as we have described above in
415 order for the autochanger to be used. Please see the
416 \ilink{Storage Resource}{Autochanger1} in the Director's chapter
418 \ilink{Device Resource}{Autochanger} in the Storage daemon
419 chapter for more details on these records.
421 Thus all stages of dealing with tapes can be totally automated. It is also
422 possible to set or change the Slot using the {\bf update} command in the
423 Console and selecting {\bf Volume Parameters} to update.
425 Even though all the above configuration statements are specified and correct,
426 Bacula will attempt to access the autochanger only if a {\bf slot} is non-zero
427 in the catalog Volume record (with the Volume name).
429 If your autochanger has barcode labels, you can label all the Volumes in
430 your autochanger one after another by using the {\bf label barcodes} command.
431 For each tape in the changer containing a barcode, Bacula will mount the tape
432 and then label it with the same name as the barcode. An appropriate Media
433 record will also be created in the catalog. Any barcode that begins with the
434 same characters as specified on the "CleaningPrefix=xxx" command, will be
435 treated as a cleaning tape, and will not be labeled. For example with:
437 Please note that Volumes must be pre-labeled to be automatically used in
438 the autochanger during a backup. If you do not have a barcode reader, this
439 is done manually (or via a script).
445 Cleaning Prefix = "CLN"
450 Any slot containing a barcode of CLNxxxx will be treated as a cleaning tape
451 and will not be mounted.
453 \section{Changing Cartridges}
454 \index[general]{Changing Cartridges }
455 If you wish to insert or remove cartridges in your autochanger or
456 you manually run the {\bf mtx} program, you must first tell Bacula
457 to release the autochanger by doing:
462 (change cartridges and/or run mtx)
467 If you do not do the unmount before making such a change, Bacula
468 will become completely confused about what is in the autochanger
469 and may stop function because it expects to have exclusive use
470 of the autochanger while it has the drive mounted.
474 \section{Dealing with Multiple Magazines}
475 \index[general]{Dealing with Multiple Magazines }
476 \index[general]{Magazines!Dealing with Multiple }
478 If you have several magazines or if you insert or remove cartridges from a
479 magazine, you should notify Bacula of this. By doing so, Bacula will as
480 a preference, use Volumes that it knows to be in the autochanger before
481 accessing Volumes that are not in the autochanger. This prevents unneeded
482 operator intervention.
484 If your autochanger has barcodes (machine readable tape labels), the task of
485 informing Bacula is simple. Every time, you change a magazine, or add or
486 remove a cartridge from the magazine, simply do
492 (insert new magazine)
498 in the Console program. This will cause Bacula to request the autochanger to
499 return the current Volume names in the magazine. This will be done without
500 actually accessing or reading the Volumes because the barcode reader does this
501 during inventory when the autochanger is first turned on. Bacula will ensure
502 that any Volumes that are currently marked as being in the magazine are marked
503 as no longer in the magazine, and the new list of Volumes will be marked as
504 being in the magazine. In addition, the Slot numbers of the Volumes will be
505 corrected in Bacula's catalog if they are incorrect (added or moved).
507 If you do not have a barcode reader on your autochanger, you have several
511 \item You can manually set the Slot and InChanger flag using the {\bf update
512 volume} command in the Console (quite painful).
514 \item You can issue a
522 command that will cause Bacula to read the label on each of the cartridges in
523 the magazine in turn and update the information (Slot, InChanger flag) in the
524 catalog. This is quite effective but does take time to load each cartridge
525 into the drive in turn and read the Volume label.
527 \item You can modify the mtx-changer script so that it simulates an
528 autochanger with barcodes. See below for more details.
532 \section{Simulating Barcodes in your Autochanger}
533 \index[general]{Autochanger!Simulating Barcodes in your }
534 \index[general]{Simulating Barcodes in your Autochanger }
536 You can simulate barcodes in your autochanger by making the {\bf mtx-changer}
537 script return the same information that an autochanger with barcodes would do.
538 This is done by commenting out the one and only line in the {\bf list)} case,
543 ${MTX} -f $ctl status | grep " *Storage Element [0-9]*:.*Full" | awk "{print \$3 \$4}" | sed "s/Full *\(:VolumeTag=\)*//"
547 at approximately line 99 by putting a \# in column one of that line, or by
548 simply deleting it. Then in its place add a new line that prints the contents
549 of a file. For example:
553 cat /etc/bacula/changer.volumes
557 Be sure to include a full path to the file, which can have any name. The
558 contents of the file must be of the following format:
569 Where the 1, 2, 3 are the slot numbers and Volume1, Volume2, ... are the
570 Volume names in those slots. You can have multiple files that represent the
571 Volumes in different magazines, and when you change magazines, simply copy the
572 contents of the correct file into your {\bf /etc/bacula/changer.volumes} file.
573 There is no need to stop and start Bacula when you change magazines, simply
574 put the correct data in the file, then run the {\bf update slots} command, and
575 your autochanger will appear to Bacula to be an autochanger with barcodes.
578 \section{The Full Form of the Update Slots Command}
579 \index[general]{Full Form of the Update Slots Command }
580 \index[general]{Command!Full Form of the Update Slots }
582 If you change only one cartridge in the magazine, you may not want to scan all
583 Volumes, so the {\bf update slots} command (as well as the {\bf update slots
584 scan} command) has the additional form:
588 update slots=n1,n2,n3-n4, ...
592 where the keyword {\bf scan} can be appended or not. The n1,n2, ... represent
593 Slot numbers to be updated and the form n3-n4 represents a range of Slot
594 numbers to be updated (e.g. 4-7 will update Slots 4,5,6, and 7).
596 This form is particularly useful if you want to do a scan (time expensive) and
597 restrict the update to one or two slots.
599 For example, the command:
603 update slots=1,6 scan
607 will cause Bacula to load the Volume in Slot 1, read its Volume label and
608 update the Catalog. It will do the same for the Volume in Slot 6. The command:
617 will read the barcoded Volume names for slots 1,2,3 and 6 and make the
618 appropriate updates in the Catalog. If you don't have a barcode reader or have
619 not modified the mtx-changer script as described above, the above command will
620 not find any Volume names so will do nothing.
623 \section{FreeBSD Issues}
624 \index[general]{Issues!FreeBSD }
625 \index[general]{FreeBSD Issues }
627 If you are having problems on FreeBSD when Bacula tries to select a tape, and
628 the message is {\bf Device not configured}, this is because FreeBSD has made
629 the tape device {\bf /dev/nsa1} disappear when there is no tape mounted in the
630 autochanger slot. As a consequence, Bacula is unable to open the device. The
631 solution to the problem is to make sure that some tape is loaded into the tape
632 drive before starting Bacula. This problem is corrected in Bacula versions
636 \ilink{ Tape Testing}{FreeBSDTapes} chapter of this manual for
637 {\bf important} information concerning your tape drive before doing the
639 \label{AutochangerTesting}
641 \section{Testing Autochanger and Adapting mtx-changer}
642 \index[general]{Testing the Autochanger }
643 \index[general]{Adapting Your mtx-changer }
646 Before attempting to use the autochanger with Bacula, it is preferable to
647 "hand-test" that the changer works. To do so, we suggest you do the
648 following commands (assuming that the {\bf mtx-changer} script is installed in
649 {\bf /etc/bacula/mtx-changer}):
653 \item [Make sure Bacula is not running.]
655 \item [/etc/bacula/mtx-changer \ /dev/sg0 \ list \ 0 \ /dev/nst0 \ 0]
656 \index[sd]{mtx-changer list}
658 This command should print:
670 or one number per line for each slot that is occupied in your changer, and
671 the number should be terminated by a colon ({\bf :}). If your changer has
672 barcodes, the barcode will follow the colon. If an error message is printed,
673 you must resolve the problem (e.g. try a different SCSI control device name
674 if {\bf /dev/sg0} is incorrect. For example, on FreeBSD systems, the
675 autochanger SCSI control device is generally {\bf /dev/pass2}.
677 \item [/etc/bacula/mtx-changer \ /dev/sg0 \ slots \ 0 \ /dev/nst0 \ 0]
678 \index[sd]{mtx-changer slots}
680 This command should return the number of slots in your autochanger.
682 \item [/etc/bacula/mtx-changer \ /dev/sg0 \ unload \ ]
683 \index[sd]{mtx-changer unload}
685 If a tape is loaded, this should cause it to be unloaded.
687 \item [/etc/bacula/mtx-changer \ /dev/sg0 \ load \ 3 \ /dev/nst0 \ 0 ]
688 \index[sd]{mtx-changer load}
690 Assuming you have a tape in slot 3, it will be loaded into the read slot (0).
693 \item [/etc/bacula/mtx-changer \ /dev/sg0 \ loaded \ 0 \ /dev/nst0 \ 0]
694 \index[sd]{mtx-changer loaded}
698 \item [/etc/bacula/mtx-changer \ /dev/sg0 \ unload]
701 Once all the above commands work correctly, assuming that you have the right
702 {\bf Changer Command} in your configuration, Bacula should be able to operate
703 the changer. The only remaining area of problems will be if your autoloader
704 needs some time to get the tape loaded after issuing the command. After the
705 {\bf mtx-changer} script returns, Bacula will immediately rewind and read the
706 tape. If Bacula gets rewind I/O errors after a tape change, you will probably
707 need to insert a {\bf sleep 20} after the {\bf mtx} command, but be careful to
708 exit the script with a zero status by adding {\bf exit 0} after any additional
709 commands you add to the script. This is because Bacula checks the return
710 status of the script, which should be zero if all went well.
712 You can test whether or not you need a {\bf sleep} by putting the following
713 commands into a file and running it as a script:
718 /etc/bacula/mtx-changer /dev/sg0 unload
719 /etc/bacula/mtx-changer /dev/sg0 load 3
720 mt -f /dev/st0 rewind
725 If the above script runs, you probably have no timing problems. If it does not
726 run, start by putting a {\bf sleep 30} or possibly a {\bf sleep 60} in the
727 script just after the mtx-changer load command. If that works, then you should
728 move the sleep into the actual {\bf mtx-changer} script so that it will be
729 effective when Bacula runs.
731 A second problem that comes up with a small number of autochangers is that
732 they need to have the cartridge ejected before it can be removed. If this is
733 the case, the {\bf load 3} will never succeed regardless of how long you wait.
734 If this seems to be your problem, you can insert an eject just after the
735 unload so that the script looks like:
740 /etc/bacula/mtx-changer /dev/sg0 unload
741 mt -f /dev/st0 offline
742 /etc/bacula/mtx-changer /dev/sg0 load 3
743 mt -f /dev/st0 rewind
748 Obviously, if you need the {\bf offline} command, you should move it into the
749 mtx-changer script ensuring that you save the status of the {\bf mtx} command
750 or always force an {\bf exit 0} from the script, because Bacula checks the
751 return status of the script.
753 As noted earlier, there are several scripts in {\bf
754 \lt{}bacula-source\gt{}/examples/devices} that implement the above features,
755 so they may be a help to you in getting your script to work.
757 If Bacula complains "Rewind error on /dev/nst0. ERR=Input/output error." you
758 most likely need more sleep time in your {\bf mtx-changer} before returning to
759 Bacula after a load command has been completed.
763 \section{Using the Autochanger}
764 \index[general]{Using the Autochanger }
765 \index[general]{Autochanger!Using the }
767 Let's assume that you have properly defined the necessary Storage daemon
768 Device records, and you have added the {\bf Autochanger = yes} record to the
769 Storage resource in your Director's configuration file.
771 Now you fill your autochanger with say six blank tapes.
773 What do you do to make Bacula access those tapes?
775 One strategy is to prelabel each of the tapes. Do so by starting Bacula, then
776 with the Console program, enter the {\bf label} command:
781 Connecting to Director rufus:8101
782 1000 OK: rufus-dir Version: 1.26 (4 October 2002)
787 it will then print something like:
791 Using default Catalog name=BackupDB DB=bacula
792 The defined Storage resources are:
795 Select Storage resource (1-2): 1
799 I select the autochanger (1), and it prints:
803 Enter new Volume name: TestVolume1
804 Enter slot (0 for none): 1
808 where I entered {\bf TestVolume1} for the tape name, and slot {\bf 1} for the
816 Select the Pool (1-2): 1
820 I select the Default pool. This will be automatically done if you only have a
821 single pool, then Bacula will proceed to unload any loaded volume, load the
822 volume in slot 1 and label it. In this example, nothing was in the drive, so
827 Connecting to Storage daemon Autochanger at localhost:9103 ...
828 Sending label command ...
829 3903 Issuing autochanger "load slot 1" command.
830 3000 OK label. Volume=TestVolume1 Device=/dev/nst0
831 Media record for Volume=TestVolume1 successfully created.
832 Requesting mount Autochanger ...
833 3001 Device /dev/nst0 is mounted with Volume TestVolume1
839 You may then proceed to label the other volumes. The messages will change
840 slightly because Bacula will unload the volume (just labeled TestVolume1)
841 before loading the next volume to be labeled.
843 Once all your Volumes are labeled, Bacula will automatically load them as they
846 To "see" how you have labeled your Volumes, simply enter the {\bf list
847 volumes} command from the Console program, which should print something like
853 Using default Catalog name=BackupDB DB=bacula
857 Select the Pool (1-2): 1
858 +-------+----------+--------+---------+-------+--------+----------+-------+------+
859 | MedId | VolName | MedTyp | VolStat | Bites | LstWrt | VolReten | Recyc | Slot |
860 +-------+----------+--------+---------+-------+--------+----------+-------+------+
861 | 1 | TestVol1 | DDS-4 | Append | 0 | 0 | 30672000 | 0 | 1 |
862 | 2 | TestVol2 | DDS-4 | Append | 0 | 0 | 30672000 | 0 | 2 |
863 | 3 | TestVol3 | DDS-4 | Append | 0 | 0 | 30672000 | 0 | 3 |
865 +-------+----------+--------+---------+-------+--------+----------+-------+------+
871 \section{Barcode Support}
872 \index[general]{Support!Barcode }
873 \index[general]{Barcode Support }
875 Bacula provides barcode support with two Console commands, {\bf label
876 barcodes} and {\bf update slots}.
878 The {\bf label barcodes} will cause Bacula to read the barcodes of all the
879 cassettes that are currently installed in the magazine (cassette holder) using
880 the {\bf mtx-changer} {\bf list} command. Each cassette is mounted in turn and
881 labeled with the same Volume name as the barcode.
883 The {\bf update slots} command will first obtain the list of cassettes and
884 their barcodes from {\bf mtx-changer}. Then it will find each volume in turn
885 in the catalog database corresponding to the barcodes and set its Slot to
886 correspond to the value just read. If the Volume is not in the catalog, then
887 nothing will be done. This command is useful for synchronizing Bacula with the
888 current magazine in case you have changed magazines or in case you have moved
889 cassettes from one slot to another.
891 The {\bf Cleaning Prefix} statement can be used in the Pool resource to define
892 a Volume name prefix, which if it matches that of the Volume (barcode) will
893 cause that Volume to be marked with a VolStatus of {\bf Cleaning}. This will
894 prevent Bacula from attempting to write on the Volume.
898 \section{Bacula Autochanger Interface}
899 \index[general]{Interface!Bacula Autochanger }
900 \index[general]{Bacula Autochanger Interface }
902 Bacula calls the autochanger script that you specify on the {\bf Changer
903 Device} statement. Normally this script will be the {\bf mtx-changer} script
904 that we can provide, but it can in fact be any program. The only requirements
905 are that the "commands" that Bacula uses are {\bf loaded}, {\bf load}, {\bf
906 unload}, {\bf list}, and {\bf slots}. In addition,
907 each of those commands must return the information in the precise format as
912 - Currently the changer commands used are:
913 loaded -- returns number of the slot that is loaded, base 1,
914 in the drive or 0 if the drive is empty.
915 load -- loads a specified slot (note, some autochangers
916 require a 30 second pause after this command) into
918 unload -- unloads the device (returns cassette to its slot).
919 list -- returns one line for each cassette in the autochanger
920 in the format <slot>:<barcode>. Where
921 the {\bf slot} is the non-zero integer representing
922 the slot number, and {\bf barcode} is the barcode
923 associated with the cassette if it exists and if you
924 autoloader supports barcodes. Otherwise the barcode
926 slots -- returns total number of slots in the autochanger.
930 Bacula checks the exit status of the program called, and if it is zero, the
931 data is accepted. If the exit status is non-zero, Bacula ignores any
932 information returned and treats the drive as if it is not an autochanger.