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MrLandShark

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VM Snapshot Files

Attached is a screen print of the "C" drive of my Exchange 07 server from the data store it lives on. I believe the files which contain "-000000x" are related to snap shots, but there were no snap shots taken at the time of the screen print. Also, some of the files are almost 2 months old.   My questions are:  Should those files be there? If not, what is the proper way to get rid of them? Could having them there cause problems?
Users have been having performance problems with Outlook when we create Replicas (using Veeam 5 Enterprise) of the Exchange Server.

Thanks for your help. User generated image
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coolsport00
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If you rt-click on the VM -> Snapshot -> Snapshot Manager. Are there a 'tree' of snaps that show, or just 1 single high-level 'disk'?

~coolsport00
If you do have many snaps in snapshot manager, you can select 'delete all' and this will remove the snapshots, and commit all data in the snapshots to the parent disk. If possible, it's best to delete (commit) the snaps while the VM is powered down, so if you can do this off-hours while down, it would be best.
Avatar of Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
A snap shot is a way to preserve a point in time when the VM was running OK before making changes. A snapshot is NOT a way to get a static copy of a VM before making changes.  When you take a snapshot of a VM what happens is that a delta file gets created and the original VMDK file gets converted to a Read-Only file.  There is an active link between the original VMDK file and the new delta file.  Anything that gets written to the VM actually gets written to the delta file.   The correct way to use a snapshot is when you want to make some change to a VM like adding a new app or a patch; something that might damage the guest OS. After you apply the patch or make the change and it’s stable, you should really go into snapshot manager and delete the snapshot which will commit the changes to the original VM, delete the snap, and make the VMDK file RW. The official stance is that you really shouldn’t have more than one snap at a time and that you should not leave them out there for long periods of time. Adding more snaps and leaving them there a long time degrades the performance of the VM.  If the patch or whatever goes badly or for some reason you need to get back to the original unmodified VM, that’s possible as well.  

I highly recommend reading these 2 articles on snaps:

Understanding Snapshots - http://kb.vmware.com/kb/1015180
Snaphot Best Practices - http://kb.vmware.com/kb/1025279
You firstly need to establish, if they are being created by the Veeam Backup and Replication application which is very likely.

Why they are not being deleted?

Also manually create a snapshot job, and see if you can delete them all.

and then look to the issue with Veeam after backup or replication jobs.

I know you have not deliberately created these snapshots, all backup applications use snapshots to perform their backups, but as Administrators, you MUST check that your Virtual Machines ARE not running off snapshot disks, for two reasons, performance, and the datastore may run out of disk space.

You can alter the location of Snapshots, to a temporary LUN or Datastore for Snapshot usage, so you'll never run out of datastore space, should snapshots be left. But I would use vCenter alarms or Nagios monitoring to watch for these hidden snapshots.
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MrLandShark

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The snapshot manager just says "You are here", no tree.
Hmm...well, it looks like it's obvious they're there :) See this KB to see if you can see any via cmd line:
http://kb.vmware.com/kb/1002310

If indeed Veeam is the culprit here, and if Veeam is installed on a VM, see if you have extra virtual (hard) disks attached to your Veeam VM (rt-click on Veeam VM -> Edit Settings -> Hardware tab).
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Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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You may want to wait to to this operation out of hours, as it could pause the Server, and it may take a few hours to complete the operation, also ensure you have enough disk space.
I created a snapshot through VM and then did a "delete all" to remove it. The snapshot that I just created was removed but the old snapshot files are still there.   Should I just manually delete them from the data store?
No...try and use the cmd line that I suggested. Or...you could try the 'Clone' function or vCenter Converter Standalone which should commit all snaps during the Clone/Convert process. Do *not* ever manually delete snapshots. You could corrupt your VM.

~coolsport00
NO NO NO, never just remove them from the datastore.
I would try to clone out the machine if possible using vCenter.
After creating a clone do I use the clone as my new Exchange Server or will the process clean out the old files from the existing server?
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just make sure you TEST TEST TEST and TEST before you delete the old version, dont powet up both on the same network, and i would suggest you keep a week before deleting the old.
I finally heard back from VMware Support. The tech logged onto my syetem and determined that the files were not being used.  They created a folder on the data store and moved the files into it.  They said that if there are no problems with the server after a few days then I could delete the folder.  There have been no problems for three days so I will delete the folder in  the morning.
Thanks for the help.
VMware support provided an alternate solution that did not require creating a clone and deleteing the original server.
Did you ask VMware Support about you other issue?

Users have been having performance problems with Outlook when we create Replicas (using Veeam 5 Enterprise) of the Exchange Server.
?
Yes.  She said that can be expected when taking snap shots of servers with high I/O.  She also said that some users use Raw Device Mapping when setting up HDD to help with the problem.   I am looking into what Raw Device Mapping is and if it might help my problem. Any thoughts?
Any thoughts? please post another question to discuss this in detail.
A new question has been posted.
Yes, I've responded with my thoughts on VMware's advice.