Snapshot Consolidation

[vipes27]

We use Veeam for backups and replication of our VMware environment. Lately, I've been getting a couple of errors on just a couple of our servers, saying that it can't do the backup because it needs snapshot consolidation, but all automatic snapshot consolidation attempts have failed. It says the most likely reason is a virtual disk being locked by some external process. Is it safe to just consolidate the snapshots during production? Thanks.

[Prakas]

It depends on version of ESXi you are using.

In case of ESX 4.x, snapshot consolidation may lead to an unexpected downtime as VM may be 'stunned' after multiple consolidate attempts.

It is safe to consolidate in case of ESXi 5.x as it won't cause long pause of the VM(by design).

If you can afford to downtime, consolidating when the VM is down is the best and quick way.

[vipes27]

We are running 5.5. Should I actually power down the vm before consolidating or just do it after hours? Thanks!

[PaulITGuy]

I use veeam 8.0 U3 on ESXi 5.5 (build 3116895) and I have getting a lot more snapshot consolidation errors than normal.

what version of veeam and you using?

I normally consolidate my snapshots during production, IF my storage system can handle the extra load and IF I understand why it won't consolidate now.

[vipes27]

We're on v8.0 as well. My guess is that there is a stale snapshot that is holding it up.

[Teddy092]

Hi vipes27‌,

I have faced this issue many times before.

Veeam actually needs to lock the vdisk of your VMs during backup. If backups run while consolidation is required, Veeam won't be able to complete the backup.

In that particular case, cancel the back up and make sure that the cancellation is done. Then you can consolidate your VM.

If consolidation doesn't work make sure that your Veeam proxy servers haven't mounted vdisk of your VM and unmount them if necessary, then you should be able to consolidate your VMs.

After doing the above, try again to backup your VM from Veeam.

Good luck.