Backup and replica reading entire disk

[ashman70]

I did some maintenance on an Exchange server today, installed a service pack and a rollup pack, nothing else. Curiously, when a replica ran afterwards, and not the first one, it decided to read the entirety of the disks. Same thing happened to a backup of the same VM. Why would it do this if no changes to the disks were made? Running Veeam 9.5

[Andreas Neufert]

Hard to say without logs.

Maybe you used vmotion with VM in shutdown mode? This reset CBT.
You can look at the logs or let our support have a look.

[ashman70]

Vmotion was not used, just curious really.

Thanks

[Andreas Neufert]

disk increase within VM config trigger CBT reset as well.

What did Job statistic say about CBT?

But maybe it was just so much changed data within the VM?

[ashman70]

Literally all I did was change the network card from vmxnet 2 to vmxnet 3 and apply a service pack and rollup to Exchange, nothing else.

[Andreas Neufert]

I guess then the vmc file change triggered the CBT reset.
Our support can look at the logs if you like, if it was a safety feature of us that has resetted the CBT or if it was VMware that did it.

I guess that you had shutdown the VM for the change. Are you sure that DRS did not migrated the VM during that time to other host?