Confused re CBT issue

[ashman70]

I have a VM with a disk that was originally created at 150GB it was then extended 50GB to 200GB, so it shouldn't be affected by the CBT bug as far as I understand?

Yet today after a backup completed I got the following error "Unable to truncate transaction logs. Details: KeepSnapshot error: [Freeze job already stopped.]" which may be unrelated.

However when I browse the datastore of this VM I do indeed find -CTK.VMDK files which tells me it is affected by the bug?

I am guess the advice is going to be a reset of the CBT on the VM regardless, but I just find it weird that its affected, if it is indeed.

[Vitaliy S.]

No, you're not affected by this CBT bug, and the error message is unrelated. Please contact our technical team to find our the reason why transaction logs cannot be truncated.

[ashman70]

Thanks Vitaly, I am just in the midst of performing an upgrade from Veeam 6.5 to 8 in the environment where this VM exists, once that is done and Veeam has run a backup on this particular VM, if I am still getting the error, I will open a case.

[ashman70]

So the existence of -CTK.VMFK files in itself is not evidence that a VM is affected by the CBT bug? What does the existence of these files mean then, if anything?

[Vitaliy S.]

These files are used to track changed block per each virtual disk file, so they will always exist if virtual disk change tracking is used. Thanks!