VHDX live resizing and Veeam (KB2450)

[wku]

Hello.

There's this old KB article: https://www.veeam.com/kb2450
It does not list specific relevant versions, of HV nor of VBR.

The shrinking scenario is described in more detail, and fails-safe.
However, the expanding scenario - which would be way more common - is a laconic "backup may become inconsistent" statement.
I read this as a promise of silent data corruption from there onwards.

Someone has asked last year in this thread,
microsoft-hyper-v-f25/resizing-vhdx-and ... 93187.html
and got a "that part [danger during expanding] should still be valid" comment from David.

Is there any chance to get some more detailed information about this problem?
Is it truly a risk of backup corruption?
Is there any way Veeam could - or already does - notice this and alarm or automatically resolve this? (by e.g. comparing VHDX size from the last backup run to current?)
And possibly most importantly - why is this buried in a KB article that's relatively hard to find, but with no warnings in the main documentation?

Thank you.

PS. Wouldn't that requirement of active full also start a new XFS/ReFS thin-copy chain, consuming full size in the repository?

[david.domask]

Hi wku,

As per the KB article, do an Active Full after expanding.

The vagueness in the KB is addressed by the requirement to run an Active Full to ensure that there is no reliance on RCT data, do a full read.

Your point regarding documentation is valid, will ask we add a warning + reference to the KB on the relevant User Guide pages.

[wku]

Thank you very much.
For the answer, and for the promise of documentation update.