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Snapshot transfer question / problem?

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I recently changed the way in which our backup system functions to provide less duplication of file copying, whilst maintaining both in-house and off-site backup recovery options.


i.e. originally I had 5 SATA disks on daily rotation, scripts ran and copied directly from the servers to the disks each day, then taken offsite.


Now, the scripts backup to a central NAS box and then second scripts copies the snapshots over to the off-site disks for removal.


The problem I'm seeing in the logs is that I seem to have a lot of files 'remaining', non completed, performance 0MB/Min yet the transfer has been deemed 'successful'.



- 17/08/2009 11:46:17: Transferring from DesktopBackups

Local Disk (C:) (17/08/2009 10:30) on Client "Sue *****"

17/08/2009 11:46:38: Execution completed successfully

Remaining: 9 files, 156.9 MB

Completed: 0 files, zero KB

Performance: 0.0 MB/minute

Duration: 00:00:20



- 17/08/2009 11:46:38: Transferring from ExchangeBackups

First Storage Group (14/08/2009 19:00) on Client "MS Exchange 2003"

17/08/2009 11:46:40: Execution completed successfully

Remaining: 3 files, 32.5 GB

Completed: 0 files, zero KB

Performance: 0.0 MB/minute

Duration: 00:00:01


X User Backup Store (14/08/2009 19:24) on Client "MS Exchange 2003"

17/08/2009 11:46:42: Execution completed successfully

Remaining: 2 files, 1.5 GB

Completed: 0 files, zero KB

Performance: 0.0 MB/minute

Duration: 00:00:01



- 17/08/2009 11:46:42: Transferring from FileserverBackup

DATA (E:) (14/08/2009 18:00) on Client "Fileserver"

17/08/2009 11:50:02: Execution completed successfully

Remaining: 427 files, 1.7 GB

Completed: 0 files, zero KB

Performance: 0.0 MB/minute

Duration: 00:03:18


Some of this data is incredably important to get an offsite copy of and I'm not sure why these files were not copied?


Other snapshot copies seem to work correctly i.e.


+ Executing Monday - Offiste Snapshots at 17/08/2009 09:36 (Execution unit 1)

To Backup Set Monday 1TB...


- 17/08/2009 09:36:38: Transferring from DomainCBackups

Local Disk (C:) (14/08/2009 19:04) on Client "Domain Controller 3"

17/08/2009 09:37:43: Execution completed successfully

Completed: 71 files, 161.9 MB

Performance: 154.1 MB/minute

Duration: 00:01:04 (00:00:02 idle/loading/preparing)



- 17/08/2009 09:37:43: Transferring from DomainCBackups

Local Disk (C:) (14/08/2009 19:00) on Client "Domain Controller 1"

17/08/2009 09:38:21: Execution completed successfully

Completed: 91 files, 179.9 MB

Performance: 291.5 MB/minute

Duration: 00:00:37


Others seem to half work i.e.


- 17/08/2009 13:02:20: Transferring from LaptopBackups

SW_Preload (C:) (14/08/2009 15:17) on Client "Pete ******* (N200)"

17/08/2009 13:04:29: Execution completed successfully

Remaining: 10 files, 15 KB

Completed: 5 files, 7 KB

Performance: 0.1 MB/minute

Duration: 00:02:09


Any ideas what's happening here? The snapshot script selector is set to all..



Edited by Guest
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Oh I should mention that to copy these snapshots I have setup a script using the 'transfer snapshot' option and within that to copy 'The most recent Snapshot for each source'.


i.e. My script should be grabbing the newest backup data for each Server, Laptop, Desktop, Exchange Store, SQL database etc and copying it over to my SATA disk.


Grooms and recataloging is also hopelessly unreliable using the NAS box (via CIFs share).



Edited by Guest
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Actually I never transfer backups... and I gave up on regular NAS* (CIFS), just not fast/reliable enough.


- Is it an option to duplicate or backup the backups the regular fashion instead of transferring? (it might be an extra step when restoring, but that would be in case of a real catastrophe).


- Can you test this without the involvement of the NAS, but with local storage? Just to check the NAS isn't the culprit.


Note: *) As a Retrospect target that is.

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Thanks for the reply Ramon. It's tough to test without NAS involvement as all my backups are now stored on this device - so I have no other snapshots to try and transfer (it copies the snapshot rather than move).


I never noticed this problem when copying from server directly to the SATA drives, so I suspect it's a Retrospect issue when using network storage.


I might set the server up as an iSCSI endpoint and see if that's any more reliable...


It's weird that the snapshot scripts KNOWS it has 'x' files to copy but doesn't seem to want to complete the copy fucntion before declaring it successful!?



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Ok, I'm getting confused now. I'm now starting to think the 'latest snapshot' doesn't contain ALL the files to restore the data.



It's unclear what you are asking. See if this explanation helps.


Under the hood, Retrospect works similar to other backup programs, with an initial "full" backup followed by "incremental" backups in a sequence of "sessions".


With other backup programs, to end up with the files that were present on a given day, you have to start from the initial "full" backup, restore that, then restore forward, in sequence, each "incremental" backup. At the end, that leaves you with the most recent version of the file.


Here is where Retrospect is different:


Retrospect's "backup set" is a database (container) that holds the initial full backup plus all subsequent incrementals (well, neglecting for the moment the issue of "grooming"). Each time a backup session is done, Retrospect makes a "snapshot" of the files that are present on the source at that time, and does an incremental backup of new / changed files.


Retrospect's "catalog" is an index of pointers into the database (backup set) to the location of each file in the current snapshot. If the file is present in the backup set from a previous backup, then Retrospect's catalog for the current snapshot points into those older backup sessions. If the file was newly backed up, then Retrospect's catalog for the current snapshot points into the current backup session.


The backup set also holds metadata (such as permissions, timestamps, etc.).


So, the "snapshot" is simply a list of the files seen on the source at the time of the backup session. If files are missing from that snapshot, then your selectors are set wrong for what files are to be captured.


Does this help?



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