I am implementing veeam 8 to backup an heterogeneous VMware infrastructure
I have all versions of VM hardware and most of my v7 and higher VMs have CBT disabled
the Infrastructure is working on vSphere 5.5 and vSphere 5.0
I was surprised that no issues appeared about cbt disabled and in the log I saw that the jobs are automaticaly enabling cbt on the VMs with v7 and higher HW
so first session the veeam reads all the disk and after only changes.
and I was surprised that with vm version 4 I have incremental backups too! the only difference is that the entire disk is read but only changes are transferred
I am very happy with that, my question is, can we estimate the time Veeam reads data (for exemple for a 100 GB disk) on a direct san transfert mode for VMs with v4 hardware?
to the question why dont you upgrade ? my response is ASAP but we cant wait the upgrade to backup VMs

thanks for answer if possible