I have about 10 databases on a server that I have in Full Recovery model and all are mirrored using Sql Server Mirroring.
My current backup strategy is as follows:
Full Backup 1am
Differential Backup every 2 hours
Transactional Log Backup every 15 minutes
The problem I have is that the differential backups are very slow for a couple of the databases, the diff backup takes roughly 11 minutes on average.
The reason for this is the databases are synced regularly with another system for a large number of rows, thus creating a large number of differences to backup.
On the flip side my transaction log backups are obviously very quick.
This has started to become a problem as at differential backup time the server is struggling with the load, in some cases causing time outs on client machines.
What are the downsides to dropping the differential backup and going with full/ transaction backups? Obviously the restore time would increase with no diff backups but then I do have mirrored databases, so should that be a concern at all?
Any thoughts would be appreciated, the server is currently running Sql Server 2005.