Regarding Incremental Backups

Hello All,


Just wanted to understand, if I take a full backup and then then lets say there are no backups for a period of time and the full backup gets expired. If I take an incremental backup now, will it backup everything or only the changes that were made after the full backup ( * The full backup has now expired from NBU catalog now). 


Will NBU backup only the changed files based on the archive bit ? 

4 Replies

Incremental schedule may kick

Incremental schedule may kick in , however it will take Full backup as , Incremental schedule doesn't have any base Full backup to maintain chain.

Based on archive bit /time stamp as per your environment design it would pick files which are best candidate for backups (Mostly it should backup all mentioned in selection)


I have never tried this - but

I have never tried this - but i expect netbackup would complain about missing full backup and make the first incremental a "full". I can't recommend this in production. But why not try it out on a test sysem for fun ?

Yes - Netbackup per default uses the archive bit. It can be changed to "file last modified" time (it's a option in the client gui on Windows systems).


If you run the incremental

If you run the incremental backup in this case it will run as a full backup. And during the next attempt when this incremental backup runs it will backup only the changes.




Incremental will run as Full

Incremental will run as Full as no full backup exists for the same backup policy.