[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Bacula-devel] Synthetic Full backup or Consolidation

* Kern Sibbald schrieb am 17.05.08 um 14:59 Uhr:
> Item  3:  Merge multiple backups (Synthetic Backup or Consolidation) 
>   Origin: Marc Cousin and Eric Bollengier 
>   Date:   15 November 2005
>   Status: 
>   What:   A merged backup is a backup made without connecting to the Client.
>           It would be a Merge of existing backups into a single backup.
>           In effect, it is like a restore but to the backup medium.
>           For instance, say that last Sunday we made a full backup.  Then
>           all week long, we created incremental backups, in order to do
>           them fast.  Now comes Sunday again, and we need another full.
>           The merged backup makes it possible to do instead an incremental
>           backup (during the night for instance), and then create a merged
>           backup during the day, by using the full and incrementals from
>           the week.  The merged backup will be exactly like a full made
>           Sunday night on the tape, but the production interruption on the
>           Client will be minimal, as the Client will only have to send
>           incrementals.
>           In fact, if it's done correctly, you could merge all the
>           Incrementals into single Incremental, or all the Incrementals
>           and the last Differential into a new Differential, or the Full,
>           last differential and all the Incrementals into a new Full
>           backup.  And there is no need to involve the Client.
>   Why:    The benefit is that :
>           - the Client just does an incremental ;
>           - the merged backup on tape is just as a single full backup,
>             and can be restored very fast.
>           This is also a way of reducing the backup data since the old
>           data can then be pruned (or not) from the catalog, possibly
>           allowing older volumes to be recycled

This sounds like a very useful Feature.

Would there be a way to combine this with some sort of data-deduplication?

Deduplication is "just" writing Metadata for a client and not
putting the data on tape because it has already been written to tape
by another client. 

Think of "hard-linking" Datablocks on tape.

Further there could be an option tp specify a minimum and a maximum
number of mediums that each data block has to be spread on.

This would bring a real "killerfeature" useful for most users into bacula 
that is offered only by commercial enterprise backup solutions so
far (AFAIK)

8AAC 5F46 83B4 DB70 8317  3723 296C 6CCA 35A6 4134

This SF.net email is sponsored by: Microsoft 
Defy all challenges. Microsoft(R) Visual Studio 2008. 
Bacula-devel mailing list

This mailing list archive is a service of Copilotco.