Beginner help with P4300s and VSS based backups - DPM

[tmitchell1981]

I was wondering if someone could give me a basic overview on how this is supposed to be structured as I'm struggling to get my backup to work.

I have 6 HP Lefthand P4300G2 SANs connected to a cluster of 4 Windows 2012 servers running Hyper-V.

I am trying to set up a new backup using DPM. I have the Application Aware Snapshot Manager Installed on the Hyper-V Servers, and it is authenticating correctly to the SANs.

This is the point where I think I may have made a mistake with the setup - The SANs are hosting a single 40TB volume which is shared to the Server Cluster over iSCSI. This works fine, and all my Virtual Servers are held on this 40TB volume.

When I try and take a backup using  DPM, I get an 'out of space' error in the event log, see below:

HP LeftHand VSS Provider: Failed to take snapshot during CommitSnapshots , 0x80001010 - Sending Multiple Operation Failed: Insufficient space to make the requested change.

It's not clear where the insufficient space is! The backup server (not HP), has plenty of space.

This is where my understanding is not good enough. Is the SAN trying to snapshot the entire 40TB volume and is this why it fails? Should I have created a separate volume for each virtual server? I've read in other guides that a single large volume is fine for a cluster.

There is 9TB of unallocated space on the SANs and the server I am trying to backup is only about 100GB. Do I need to allocate this space in some way maybe? The 40TB volume is fully provisioned.

If anyone can spot my error I would be grateful. I'm quite new to setting up SANs and clusters, and the instructions give you little information on the overall structure.

[Sbrown]

I had this happen once, it was the vm free space.

Check this link out: http://social.technet.microsoft.com/Forums/en-US/a2ed4011-ce46-465c-bcb6-ecf2f34ff43b/dpm-2010-backup-hyperv-vss-error-id-30115?forum=dpmhypervbackup

IIRC there was a snippet somewhere about clusters, but i'd start with (IN VM) VSS provider list, check version, ensure it is up to date (!!), check credentials. Empty trash, make sure all volumes have enough space.

If the machine has been restored and has that small partition for alignment/bitlocker, that can cause problems. After a restore, it was 99% full, and it sure did take me a while to figure out since it had no drive letter, everything was hidden.

There should be an eventvwr log on the VM for every VSS (fail or good)!

Myself, I just went with Veeam. With it's awesome integration, tape support, it might be easier to just backup with Veeam, then backup the backup using DPM :) no joke!

Veeam has special-sauce to work with lefthand/storevirtual to handle VSS Snapshots. I know that is not much help.

I feel your pain buddy!

[tmitchell1981]

Thanks for the reply. I'm going to take your advice and give Veeam a go as despite following your suggestions I am still stuck with the 'Insufficient Space' error althought the VM has loads of space. I removed the 100mb partition, but that had no effect.

Also I'm a bit confused, as the VSS writer runs on the host, not the VM itself. The VM isn't directly connected to the SAN. Very confusing.

Will let you know how I get on with Veeam. Will probably be back for more help!

[Sbrown]

Probably best to contact HP support for DPM. Every backup program is complex.

VSS writers all behave similar, they run under Microsoft's rule, so don't be surprised if the same VSS error shows up on (any other software). VSS runs on the VM MAN! not the host!

Account under which VSS writer runs.

MMC Access to services for VSS with 2008+ they added some security bits to protect you.

ie. http://www.veeam.com/kb1794

These solutions are similar. Before you go deleting or changing things, I strongly suggest you query support for solutions before making changes. That is what they are there for.

(but if you google around the solutions for vss problems, the solutions are almost always nearly identical! Lol)