Large Repository Drive on Hyper-V host

[HMwkr]

I am puzzled.

I have a physical backup/management server GM4 running 2012R2, with Veeam running in a 2012R2 VM, backing up our VMs on our main data server GS3 plus two VMs on GM4. GM4 has an 18TB drive on which is a Veeam repository. I have been using VEB to back up GM4's C drive and system reserved drive, excluding the repository drive. All has been working well for two years.

This weekend I added a 90TB DAS to GM4. VEB backup failed, as did backups of the two VMs running on GM4.

I found I could create volume snapshots on the individual volumes using the Windows GUI, and that I could use VEB to back up just the GM4's C, or GM4's system reserved drive, but not both.

When I reduced the volume on the repository DAS to 50TB, all backups started working again.

I understood that 2012R2 has a volume limit of 64TB, and over that chkdsk and VSS stop working - but I thought that provided I wasn't actually backing up the 93TB DAS volume itself, the other volumes would be unaffected - and being able to snapshot and back up individual drives supports that (a bit).

So am I wrong? Is it the case that the mere presence of a >64TB volume on a host, stops all Veeam VM backups working, and stops VEB host multi-drive backups working even when the >64TB volume is excluded?

Thanks in anticipation
William

[Mike Resseler]

Hi,
If I understand this correctly, the problem is with Veeam Endpoint Backup and not with Veeam Backup & Replication. Correct?

I am not sure if your use case is actually possible. The way VSS works (even if you exclude a volume) is that it will enumerate all before taking the actual snapshot. Maybe this is causing the issue.

So 2 questions:

1. Can you split up that 93TB DAS volume or is that not a possibility?
2. Can you log a case with our support team so we get the definitive answer to whether it works or not

I know you stated that creating a volume snapshot on an individual volume with Windows GUI works, but that is not completely the same as what VEB is doing. Yes, we are creating a snapshot, but a bit differently as the snapshot through Windows UI has limitations which won't allow us to transport it to a backup media for example. (Or do many other things you expect from a backup solution)

Let us know
Mike

[HMwkr]

a) both VB&R and VEB have the problem
b) if the four volumes are V1 : system reserved, V2 : OS, V3 : data, and V4 : >64TB repository, then VEB works if I select only V1, and works if I select only V2, but fails if I select V1 and V2.
c) I wonder therefore if VB&R would successfully back up a VM all of whose components were on one host drive (eg V2 : OS; - currently my VMs have VHDs on V3 : data), but I can't test this at the moment.
d) for now I have split the DAS into two volumes, but this is a disappointing workaround.
e) I will raise a support case.

Regards
William

[Mike Resseler]

William,

Please add the support case number here as well and the follow-up with support.

Thanks a lot
Mike

[HMwkr]

Case #01996105. Veeam tech did not engage meaningfully. My conclusion FWIW:

Veeam 9.0/9.5 for Hyper-V on 2012R2 may support a >64TB volume as a Veeam repository, but the server to which that >64TB volume is attached cannot be backed up by VEB (even if VEB excludes the >64TB volume(*)), nor can Hyper-V VMs on that server be backed up by VB&R (even if the >64TB volume has no Hyper-V involvement).

(*) although VEB can back up a single volume successfully, but not multiple volumes (eg OS + recovery), which is frustrating because this suggests that VEB can work without using those VSS functions which fail in the presence of a >64TB volume, which suggests that VB&R could work without using those VSS functions which fail in the presence of a >64TB volume - for VMs which only involve a single volume on the host, for example.

Oh well.

Regards
William

[nmdange]

You could test this using the native Windows Server Backup to do a bare metal backup. If that also fails then it's a general Windows issue. What I do (and you might consider) is run Veeam itself within a VM and the Hyper-V host acts only as a backup repository and off-host proxy. In that case, taking a backup of the physical host is not particularly important since it would not take that much to just reinstall the OS.

[HMwkr]

What I do (and you might consider) is run Veeam itself within a VM and the Hyper-V host acts only as a backup repository and off-host proxy. In that case, taking a backup of the physical host is not particularly important since it would not take that much to just reinstall the OS.

That is my (client's) setup: Veeam in a VM on this host to which I have recently added a >64TB volume to be an additional Veeam repository.

Obviously I want/need to keep backing up the Veeam VM. If the additional repository is >64TB all VB&R VM backups fail, and so does the VEB backup of the host (unless I back up only the OS drive - if I back up OS and system recovery drives, VEB fails). NB these failing backups do not use the new >64TB repository, and all work if the >64TB volume is shrunk to <64TB.

This being a relatively small client, we don't want to have to buy a separate physical server just to handle the >64TB repository.

Regards
William