SUMMARY
Provides steps to resolve the issue where VMware incremental/differential backups were unnecessarily being replaced by full backups.
ISSUE
VMware incremental/differential backups were unnecessarily being replaced by full backups.
When performing VMware Incremental/Differential Backups, we keep a track of a hardware hash. If, on the next Incremental/Differential, this hardware hash is found different than the previous one, then, that Backup fails and the next Backup is promoted to a natural Full.
This hardware hash is calculated using certain virtual hardware (VMDKs, ethernet card, RAM, CPU, etc.) of the VM. There might be some virtual hardware that is not required in this calculation.
Eg: If the RAM on the VM is changed, then, the Incremental/Differential should continue to succeed without the requirement of a new Full
RESOLUTION
Upgrade to version 9.1.0 or later of the Unitrends software.
CAUSE
A known bug in a version previous to 9.1.0.