I am having problems with my synthetic fulls bloating to ~3x their expected size.
My total data to backup is ~250GB (compressed), but my fulls are now ~750GB in size.
I can see that during the synthetic full backup it copies close to 750GB of data, then adds the a small amount of additional data for the current month.
I’m thinking maybe it’s my retention settings, but I’m not sure why.
My intention for retention is to keep fulls & incrementals for the last 3 months.
Here are my retention settings:
The reason I specify 3 months for ‘Keep files for’ AND 3 months for the monthly GFS settings is that this is a dry run for enabling MSP360 managed Compliance Immutability. My understanding is Immutability functions based on the GFS settings only.
Based on those settings, what I’m expecting to happen is:
Synthetic fulls pull ~250GB of required data from the last month’s full backup and result in an ~250GB full backup
Fulls and incrementals are kept for 3 months
To me,it’s almost like the backup is interpreting my settings as ‘Include the last 3 monthly fulls in every monthly backup, because you want to keep them for 3 months’.
My expectation is that it would achieve this by keeping the old monthly backup files on the storage as they are, not roll them all into the current month as well.
The only other factor in all of this is that I have a 90 day compliance object lock on the storage BUCKET, so maybe it’s expecting to be able to delete something and it can’t??
That confirms my understanding of how the policies work in general [reply=“Alexander Negrash;10613”],
However, my main issue is the tripling of the size of the full backup. As far as I can see this shouldn’t be happening. Do you have any ideas as to what might be going on here?
Just so you know, I am running daily incrementals and monthly fulls, with no intermediate weekly fulls.
I don’t have the history of the initial full backups to show the bloat as it progressed, but this month there was an error during the full backup and when I manually initiated one, it couldn’t link to the previous generations so started again with a new generation from scratch.
This is why I noticed the big size discrepancy, given that it was backing up exactly the same files via the same backup job.
[reply=“SamboNZ;10631”] This looks odd. Can you please DM me your contact email address, and I will involve one of our engineers to investigate this further?
