TSM failed to incremental backup a VM, it ran a full backup instead.
The CBT (Changed Block Tracking) feature is set to off in the VM settings
Run ‘show vm all’ in dsm client console to confirm the settings – changeTracking: Off
Connect to VCenter and right click the target VM, then choose Edit Settings > Options > Advanced/General > Configuration Parameters and set ctkEnabled = “TRUE”
* According to IBM, the value should be automatically set by TSM after the first full backup of the VM. But in my case, it did not happen.