Re: [Bacula-users] bacula can't make use of multi drives

For the sake of sharing information I am going to reply to this thread since I am working on the same type of setup and experiencing similar issues.

I removed the setting ‘prefer mounted volumes = no' and separated my jobs into 3 different pools. All my jobs are running smoothly now, no failures. The prefer mounted volumes was the issue.

Now I am experiencing interleaving on a single volume/tape drive with multiple jobs scheduled at the same time, in the same pool, as opposed to bacula using different volumes and different drives for jobs scheduled at the same time for the same pool.

Here is my issue:

I have 10 jobs that kick off at the same time every day. Each job takes anywhere from 10 minutes to 2 hours. The pool behind these jobs has 4 tape drives and 4 volumes(virtual tapes) assigned to it. The 10 jobs all kick off at the same time and they all write to the same volume, apparently(assuming) interleaving the data. See my paste below, Ive bolded start times, end times, pools and tapes. One can see these jobs all completed near each other and ran for over an hour. All to the same tape/volume, tape3 and volume AAAACF5F6A . I assume if I had the "prefer mounted volume=no" for these jobs they would use all 4 drives in the pool and write to separate volumes as opposed to interleaving to a single drive and volume. But based on the manual, reported problems and experienced problems with ‘prefer mounted volumes = no’ I hesitate to use that.

My question:

Is there another way to get multiple jobs scheduled at the same time to run concurrently using different drives and volumes, as assigned to the pool, versus all writing at the same time and interleaving the data to a single drive and volume even though the pool has 4 drives/volumes assigned to it? Or is prefer mounted volumes = no the only way to solve this?

any help is greatly appreciated

19-Nov 10:06 backup02-sd JobId 925: Job write elapsed time = 01:01:23, Transfer rate = 1.489 M Bytes/second

19-Nov 10:06 backup02-dir JobId 925: Bacula backup02-dir 5.2.6 (21Feb12):

Build OS: x86_64-pc-linux-gnu ubuntu 14.04

JobId: 925

Job: labsdb1.2014-11-19_09.05.00_21

Backup Level: Full (upgraded from Differential)

Client: "labsdb1" 2.4.4 (28Dec08) x86_64-pc-linux-gnu,debian,lenny/sid

FileSet: "Database Backup" 2014-11-07 22:02:50

Pool: "database" (From Job resource)

Catalog: "MyCatalog" (From Client resource)

Storage: "Tape3" (From Pool resource)

Scheduled time: 19-Nov-2014 09:05:00

Start time: 19-Nov-2014 09:05:02

End time: 19-Nov-2014 10:06:26

Elapsed time: 1 hour 1 min 24 secs

Priority: 10

FD Files Written: 2

SD Files Written: 2

FD Bytes Written: 5,486,802,781 (5.486 GB)

SD Bytes Written: 5,486,802,988 (5.486 GB)

Rate: 1489.4 KB/s

Software Compression: None

VSS: no

Encryption: no

Accurate: no

Volume name(s): AAAACF5F6A

Volume Session Id: 155

Volume Session Time: 1415816791

Last Volume Bytes: 1,348,311,508,992 (1.348 TB)

Non-fatal FD errors: 0

SD Errors: 0

FD termination status: OK

SD termination status: OK

Termination: Backup OK

19-Nov 10:06 backup02-dir JobId 925: Begin pruning Jobs older than 1 year .

19-Nov 10:06 backup02-dir JobId 925: No Jobs found to prune.

19-Nov 10:06 backup02-dir JobId 925: Begin pruning Files.

19-Nov 10:06 backup02-dir JobId 925: No Files found to prune.

19-Nov 10:06 backup02-dir JobId 925: End auto prune.

19-Nov 10:41 backup02-sd JobId 919: Job write elapsed time = 01:36:26, Transfer rate = 2.570 M Bytes/second

19-Nov 10:41 backup02-dir JobId 919: Bacula backup02-dir 5.2.6 (21Feb12):

Build OS: x86_64-pc-linux-gnu ubuntu 14.04

JobId: 919

Job: shopd1.2014-11-19_09.05.00_15

Backup Level: Full (upgraded from Differential)

Client: "shopdb1" 5.0.2 (28Apr10) x86_64-pc-linux-gnu,debian,squeeze/sid

FileSet: "varlibDatabase Backup" 2014-11-06 20:20:52

Pool: "database" (From Job resource)

Catalog: "MyCatalog" (From Client resource)

Storage: "Tape3" (From Pool resource)

Scheduled time: 19-Nov-2014 09:05:00

Start time: 19-Nov-2014 09:05:00

End time: 19-Nov-2014 10:41:26

Elapsed time: 1 hour 36 mins 26 secs

Priority: 10

FD Files Written: 3

SD Files Written: 3

FD Bytes Written: 14,875,191,024 (14.87 GB)

SD Bytes Written: 14,875,192,011 (14.87 GB)

Rate: 2570.9 KB/s

Software Compression: None

VSS: no

Encryption: yes

Accurate: no

Volume name(s): AAAACF5F6A

Volume Session Id: 149

Volume Session Time: 1415816791

Last Volume Bytes: 1,375,507,574,784 (1.375 TB)

Non-fatal FD errors: 0

SD Errors: 0

FD termination status: OK

SD termination status: OK

Termination: Backup OK

19-Nov 10:41 backup02-dir JobId 919: Begin pruning Jobs older than 7 years .

19-Nov 10:41 backup02-dir JobId 919: No Jobs found to prune.

19-Nov 10:41 backup02-dir JobId 919: Begin pruning Files.

19-Nov 10:41 backup02-dir JobId 919: No Files found to prune.

19-Nov 10:41 backup02-dir JobId 919: End auto prune.

19-Nov 11:10 backup02-sd JobId 917: Job write elapsed time = 02:05:32, Transfer rate = 3.894 M Bytes/second

19-Nov 11:10 backup02-dir JobId 917: Bacula backup02-dir 5.2.6 (21Feb12):

Build OS: x86_64-pc-linux-gnu ubuntu 14.04

JobId: 917

Job: pushdb.2014-11-19_09.05.00_13

Backup Level: Full (upgraded from Differential)

Client: "pushdb1" 5.0.2 (28Apr10) x86_64-pc-linux-gnu,debian,6.0.6

FileSet: "varlibDatabase Backup" 2014-11-06 20:20:52

Pool: "database" (From Job resource)

Catalog: "MyCatalog" (From Client resource)

Storage: "Tape3" (From Pool resource)

Scheduled time: 19-Nov-2014 09:05:00

Start time: 19-Nov-2014 09:05:00

End time: 19-Nov-2014 11:10:33

Elapsed time: 2 hours 5 mins 33 secs

Priority: 10

FD Files Written: 2

SD Files Written: 2

FD Bytes Written: 29,334,385,684 (29.33 GB)

SD Bytes Written: 29,334,385,894 (29.33 GB)

Rate: 3894.1 KB/s

Software Compression: None

VSS: no

Encryption: no

Accurate: no

Volume name(s): AAAACF5F6A

Volume Session Id: 147

Volume Session Time: 1415816791

Last Volume Bytes: 1,397,835,371,520 (1.397 TB)

Non-fatal FD errors: 1

SD Errors: 0

FD termination status: OK

SD termination status: OK

Termination: Backup OK

19-Nov 11:10 backup02-dir JobId 917: Begin pruning Jobs older than 1 year .

19-Nov 11:10 backup02-dir JobId 917: No Jobs found to prune.

19-Nov 11:10 backup02-dir JobId 917: Begin pruning Files.

19-Nov 11:10 backup02-dir JobId 917: No Files found to prune.

19-Nov 11:10 backup02-dir JobId 917: End auto prune.

19-Nov 11:26 backup02-sd JobId 915: Job write elapsed time = 02:21:25, Transfer rate = 3.655 M Bytes/second

19-Nov 11:26 backup02-dir JobId 915: Bacula backup02-dir 5.2.6 (21Feb12):

Build OS: x86_64-pc-linux-gnu ubuntu 14.04

JobId: 915

Job: ecommdb1.2014-11-19_09.05.00_11

Backup Level: Differential, since=2014-11-08 09:05:03

Client: "ecommdb" 2.4.4 (28Dec08) x86_64-pc-linux-gnu,debian,lenny/sid

FileSet: "Database Backup" 2014-11-07 22:02:50

Pool: "database" (From Job resource)

Catalog: "MyCatalog" (From Client resource)

Storage: "Tape3" (From Pool resource)

Scheduled time: 19-Nov-2014 09:05:00

Start time: 19-Nov-2014 09:05:00

End time: 19-Nov-2014 11:26:27

Elapsed time: 2 hours 21 mins 27 secs

Priority: 10

FD Files Written: 1

SD Files Written: 1

FD Bytes Written: 31,016,183,168 (31.01 GB)

SD Bytes Written: 31,016,183,295 (31.01 GB)

Rate: 3654.6 KB/s

Software Compression: None

VSS: no

Encryption: no

Accurate: no

Volume name(s): AAAACF5F6A

Volume Session Id: 145

Volume Session Time: 1415816791

Last Volume Bytes: 1,407,107,681,280 (1.407 TB)

Non-fatal FD errors: 0

SD Errors: 0

FD termination status: OK

SD termination status: OK

Termination: Backup OK

From: "heitor AT bacula.com DOT br" <heitor AT bacula.com DOT br>
Date: Wednesday, November 19, 2014 at 9:03 AM
To: Josh Fisher <jfisher AT pvct DOT com>
Cc: "bacula-users AT lists.sourceforge DOT net" <bacula-users AT lists.sourceforge DOT net>
Subject: Re: [Bacula-users] bacula can't make use of multi drives

I think that the only problem with setting "Prefer Mounted Volumes = no" is that it will result in a lot of moving of a volume back and forth between drives. While it might not be a bug, since it works as advertised, it CAN be a problem. For tape, it will really slow things down because it takes a substantial time to move a tape out of one drive and into another. For disk virtual autochangers, though, the moving between "drives" is simply closing a disk file and then re-opening it, meaning that the delay is very negligible.

Mr. Fisher: It's not just that. Eventually "Prefer Mounted Volumes = no" messes up the autochanger during a random backup and you have to restart storage daemon and sometimes powercycle the tape library.

If there is some other issue, like a race condition that I am not aware of, then that would indeed be a bug in my book. But I have used PreferMountedVolumes=no for disk virtual autochanger without (so far) encountering any such problems, just the swapping between drives. And for disk virtual autochangers, I don't see that as a problem in and of itself.

I don't know if it is already fixed or if this error happens for all autochangers. But last Bacula System Community Storage whitepapers goes in the same way. Having 2 pools is still safer and more reliable way to do multiple volumes writing.

Regards,

=========================================================================
Heitor Medrado de Faria - LPIC-III | ITIL-F

Faltam poucos dias - Treinamento Telepresencial Bacula: http://www.bacula.com.br/?p=2174

61 2021-8260 | 8268-4220

Site: www.bacula.com.br | Facebook: heitor.faria | Gtalk: heitorfaria AT gmail DOT com

==========================================================================

De: "Josh Fisher" <jfisher AT pvct DOT com>
Para: bacula-users AT lists.sourceforge DOT net
Enviadas: Quarta-feira, 19 de novembro de 2014 14:52:42
Assunto: Re: [Bacula-users] bacula can't make use of multi drives

On 11/19/2014 11:10 AM, heitor AT bacula.com DOT br wrote:

Is it a bug that bacula cannot write to multiple drives for the jobs in the same pool? Will there be a fix. Back in March 2014 Wolfgang Denk wrote "it can" but how?

http://adsm.org/lists/html/Bacula-users/2014-03/msg00212.html

It's not a bug, but just the way it's designed.

"Prefer Mounted Volumes=no" it's a directive that could allow to write multiple volumes within the same pool at the same time, however this is a little buggy and not recommended at this time.

It's not a bug, but it is a little buggy??

I think that the only problem with setting "Prefer Mounted Volumes = no" is that it will result in a lot of moving of a volume back and forth between drives. While it might not be a bug, since it works as advertised, it CAN be a problem. For tape, it will really slow things down because it takes a substantial time to move a tape out of one drive and into another. For disk virtual autochangers, though, the moving between "drives" is simply closing a disk file and then re-opening it, meaning that the delay is very negligible.

If there is some other issue, like a race condition that I am not aware of, then that would indeed be a bug in my book. But I have used PreferMountedVolumes=no for disk virtual autochanger without (so far) encountering any such problems, just the swapping between drives. And for disk virtual autochangers, I don't see that as a problem in and of itself.

Regards,

=========================================================================
Heitor Medrado de Faria - LPIC-III | ITIL-F

Faltam poucos dias - Treinamento Telepresencial Bacula: http://www.bacula.com.br/?p=2174

61 2021-8260 | 8268-4220

Site: www.bacula.com.br | Facebook: heitor.faria | Gtalk: heitorfaria AT gmail DOT com

==========================================================================

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