VM is backed up twice after moving back from DR site

[namiko78]

We have a replication tool for DR called Zerto. When we failover to DR site, it removes the VM from my main datacenter. That is fine. When I move it back to the origional site, veeam seems to be detecting it as a different VM and backs the entire thing up again. Some kind of unique ID that is changing? Any way to avoid this?

Thank you

[PTide]

Every time you delete and recreate a VM it gets another morefID therefore such VM is treated by Veeam as a new one, nevertheless it's fully identical to the deleted one, and the full backup/replica is performed due to the absence of CBT data for that new VM. If you want to avoid that prevent the deletion of original VM.

Thank you.

[namiko78]

I had thought that the extra blocks would be removed via deduplication, but then read that veeam only does this per restore point, not across the chain. Would be a nice feature to have it go across the chain. any pros / cons to this?

[foggy]

In this case an older restore point could not be deleted according to retention policy, since it could contain blocks that belong to other restore points as well.

[namiko78]

I didn't consider that. Good point. Thanks

[foggy]

That said, with reverse incremental mode the data will indeed be deduplicated, since will be written into the same full backup file.