Deduplication Data Consistency
In the CommCell environment, if deduplication is enabled for any storage policy, the following three components need to be synchronized:
- CommServe Database
- Deduplication Database (DDB)
- Data blocks on Disk
There might be circumstances where these three components can be out-of-sync. These scenarios could be:
- CommServe disaster recovery (DR) restore
Restoring from previous DR backup might cause both CommServe database and the DDB out-of-sync and might result in backup failures.
- Unplanned shut down of the MediaAgent hosting the DDB
When backups are running, the signatures of the backups are stored in the DDB. If there was unplanned shutdown of the MediaAgent hosting that DDB, the DDB and disk will become out-of-sync and result in backup failures.
- Backup disk has unreadable or missing data
The DDB pointing to data blocks that are unreadable or missing, might result in restore or Auxiliary Copy job failures.
To keep these three components synchronized: