Vmware Snapshots

[mbanusife]

Looking for experiences with Vmware snapshots. I have had some bad experiences with it in the past when combined with backup and restore of VMs that have snapshots associated with it. Does anyone have any comments on their experiences/successes/failures, etc...???

[COS]

We typically will not backup anything that has a snapshot. A snapshot is already a point in time which is exactly what a backup is. So why snapshot in the first place? I would recomend if Server admins need to test something on a VM, have them test it then give them a deadline to confirm it works to remove the snapshot. We backup on nearstore drives (much faster) then to tape (Slow Archive).

[GarionBrown]

You are correct in regards to backups having issues with snapshots. Most backup solutions will fail if a snapshot is present, ie VCB.

[kix1979]

There is no reason that backup of snapshots should cause the VM to be unrecoverable. The biggest thing is to grab the snapshot tree hierarchy. As long as you are grabbing that and all of the snapshots you want, everything is fine. We have customers using our products to backup entire trees several levels deep with no issues.

[Bastien_P]

Hi.

For my point of view. Snapshot are a great TEST tool. you have a patch to implement on a server and want to test it. Do a snapshot, install, test and than DELETE the snapshot!

Same with prod server. If you dont allow snapshot to grow to big and to old. I would not expect any problem.

I had two bad experience with snapshot:

1- it was a oracle server with multiple multiple snapshot. The oracle admin delete lot of snapshot while the server was up.. and eventuelly it did get corrupted and some snapshot where lost and the server had to be rebuilt. lesson: dont let snapshot go to old.

2-snapshot takes space..... and more space when you delete them... So i did add some problem at some point where one of my lun didnt had enough space to permit a delete of a snapshot... and no more space to add other thing. ooops. lesson: dont let snapshot go to big/old (since they grow with time).

Since i follow these two principle and check how snapshot are use by my server admin i didnt run into any trouble.

[COS]

"We have customers using our products to backup "...

What product is that? Just curious.

So your saying that you are backing up and backing snapshots regularly?

Hummm...

Backing up a backup sounds kind of redundant.

[Bastien_P]

Well... that one thing i learn... Snapshots are NOT a backup... Or should we say a long term backup tool. Since it can become corrupted and than you have your server admin all over your back!

[dsanders]

I don't consider snapshots to be a backup. To me backups are something that allow you to recover data if the original is lost. Snapshots are stored in the same location as the original so if you lose the original you also lose the snapshots.

Snapshots allow you to roll back to a point in time. For vmware they come into play concerning backups because they free the vmdk to allow another process to copy the vmdk to a secondary location.

[kix1979]

As others have said, snapshots are not really meant to be backups themselves. Typically, the snapshots are data points for testing or some purpose. When I say we back them up, we backup the VMDK files and the snapshots, all together. As for the company, I work for Vizioncore.

Kix

[petedr]

I agree with what you are saying about it being a great test tool. For many years I was responsibile for an Oracle environment and used snapshots or at one time non-persistent disks in GSX to test patches ( this still was in a dev or test environment ) or other coding changes.

Also agree that snapshots are not a backup method and you probably wouldn't want to keep snapshots around for long periods of time especially for large, heavy use VMs. On current backup products the esXpress product does not support backups of VMs with snapshots in its new 3.1 beta for those who have that requirement.

[petedr]

Was reading through recent posts that I have and saw I mistyped in this post.

The newest beta of esXpress Does support backups of VMs with snapshots ( Snap on Snap Mode )