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Block based backups incrementals show up as full in mminfo?

I'm working on scripts to clone our backups, and using mminfo to select saveset IDs for cloning.

We are using agent block based backups on our standalone Windows 2012 R2 servers, because their are very many small files, we don't need to index hundreds of thousands into the millions of these small files.

When I run mminfo to select full backups that ran over the weekend  (2 days, Friday & Saturday) I get duplicates for these savesets... Friday night backups are Full backups, Saturday are Incremental, and the email of the backup run says so too, but mminfo shows the Full backup saveset runs AND the incremental saveset runs as "Full".

This is in the results email:

devsedarc0.ciesin.columbia.edu:F:\, level=incr, size 3741 GB, duration 0 hours 18 minutes 29 seconds, 1 files

But I can see the mminfo output from this query:

mminfo  -q "savetime<06/30/2018 23:59:59,savetime>06/29/2018 00:00:00,level=full"  > /tmp/sslist.txt

grepped for devsedarc0:

VLAN37.001     devsedarc0.ciesin.columbia.edu 06/30/2018 3741 GB full F:\

Note that the size, 3741 GB matches the incremental line from the email...

Is this a feature or an annoyance?

Edit -- Networker version 9.1 ... target is Data Domain 6300.

Message was edited by: David Strom

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Re: Block based backups incrementals show up as full in mminfo?

For Block Based Backups to work, the full and incremental backups need to reside on the same target ddboost device to be able to calculate the changed blocks. Have one device only should be pool where BBB are written to. Just after incremental backup to Data Domain boost device, NetWorker always merges last full backup and current incremental backup. The merge is performed directly on Data Domain and is called VSF. Media data base reports Full backup every time and we can restore from any last incr There is no need to restore from the last full and subsequent incremental backups to reach the desired recovery point. - Virtual full backups apply only to the Data Domain devices. When you perform an incremental backup to a Data Domain device, you perform the backup as a virtual full backup. However, the type of the backup that you have performed is displayed as full. A virtual full backup backs up only the changed blocks from its previous full backup while referencing the unchanged blocks to the corresponding blocks of the previous full backup

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Re: Block based backups incrementals show up as full in mminfo?

I agree with what Aijaz has written.

Because of VSF on DD (DDBOOST) it will always show as FULL, even though the backup is incremental.

  • Virtual Synthetic Full brings to NetWorker a Full-Forever capability.  

   A virtual synthetic full (VSF) backup is the same as a synthetic full backup, except that it is performed on a single Data Domain system.


Similar to synthetic full, VSF uses full and partial backups to create a full backup. However, since the backup occurs on a Data Domain system using DD Boost APIs, the backup does not require save set data to be sent over the network. The result is improved performance over synthetic full and traditional full backups.

Hope it helps, David. I think we have worked together, haven't we.