Why am I seeing differential backups when none are scheduled?
Explain why unscheduled differential backups are running.
The system synthesizes differential backups in these cases:
- You have an active archive schedule containing incremental backups. Incrementals are not archived directly. Instead, the system synthesizes incrementals into a differential for archiving.
- You are vaulting incremental backups. Incrementals are not vaulted directly. Instead, the system synthesizes incrementals into a differential for legacy vaulting.
- You are using an incremental forever backup strategy. Because the schedule runs only incrementals after the first successful master, the system synthesizes both masters and differentials from the incrementals to improve restore speed. If synthetics were not created, the restore process would have to roll up all incrementals that occurred up to the restore point before performing the restore.
To verify that the differential has been synthesized by the system, check for Synthesized true in the backup details as described in To view backup details.
For more on synthesis, see this article: When are synthetic backups created?