Upgrade vSphere from 5.5 to 6, rescan disks?

[BackupDude]

Greetings,

We are in the planning phase to upgrade our vSphere environment from 5.5 to 6 update 1b. We are currently using Veeam 9 update 1 to back up this environment. My question is around post vSphere migration.

Will Veeam perform a full scan of the virtual hard disk instead of the typical nightly delta scan? My initial thought process is pointing to yes since CBT might reset due to the upgrade forcing Veeam to rescan the entire disk looking for changes. I would prefer not to rescan all disks due to the volume of data but it can be accommodated if necessary.

Any thoughts on this subject would be greatly appreciated. Thanks

[foggy]

Fabio, will it be an in-place upgrade or migration to a clean environment?

[BackupDude]

We will do an in-place upgrade of our hosts and vCenter.

[foggy]

In this case VM IDs shouldn't change (provided no re-registration in virtual infrastructure occurs) and your jobs should continue to run normally.

[BackupDude]

Thanks Foggy for the quick reply. I assume if I wipe the hosts and re-install ESXi fresh, a complete rescan would occur. vCenter would remain as an in-place upgrade.

[foggy]

Yes, upon registration in vCenter your VMs will get new IDs, which will result in full backup/replication job runs after that. If you could do maintenance host by host, for example, temporarily migrating VMs from the re-installed host, you could probably avoid this.