Strange snapshot behaviour - ESXi 5.5 creates "twoGbMaxExtentSparse" snapshots without having loaded the multiextent module

[continuum]

This was a fresh installation of ESXi 5.5.
A first VM was created and it was running without issues.
Veeam was installed and then the first run of Veeam 6.5 created a split snapshot which could not be removed after the backup.

Trying to cleanup produced very strange results.
The directory /dev/deltadisks was populated with a bunch of files like randomnumber-vmdkname-s001.vmdk.

A second disk of the same VM did not produce the same behaviour.

The final result was that the first vmdk was completely lost and had to be restored from a previous backup that was created with Acronis.

Has anyone seen somethoing like this before ?

[a_p_]

That's indeed strange, because ESXi doesn't support this .vmdk format anymore (without allowing it manually). Anyway, afaik support for ESXi 5.5 has been added with Veeam version 7.x, so this might be a result of e.g. an API call which wasn't handled (refused) properly.

André

[continuum]

Its a pity I could not keep the situation like it was and had to fix it. Next time I run into obscure snapshot behaviour I add a look into /dev/deltadisks to my troubleshooting routine.