Powershell Snapshot managemnt

[TomLon]

I have a need to create a snapshot of a VM (Esx vSphere 4.0 upd 1) everyday. I would like to keep two days of snapshots for these VMs. Meaning, a script that will delete/commit the snapshots that are older than two days. What can I do to accomodate this? Thanks

[LucD · Accepted solution]

You could do something like this

If you schedule this script to run daily, it will

*) create a new snapshot

*) remove all snapshots in excess of $targetSnaps

$vmName = <vm-name>
$targetSnaps = 2

$vm = Get-VM -Name $vmName

# Create daily snapshot
$vm | New-Snapshot -Name ($vmName + " " + (Get-Date).ToShortDateString())

# Remove excess snapshots
$snaps = $vm | Get-Snapshot | Sort-Object -Property Created -Descending
if($snaps.Count -gt $targetSnaps){
   $targetSnaps..($snaps.Count - 1) | %{
      $snaps[$_] | Remove-Snapshot -Confirm:$false
   }
}

____________

Blog: LucD notes

Twitter: lucd22

[Zsoldier]

So you would need to run a powershell by using scheduled tasks on a daily basis to have the snapshot taken, then you can either run the clean up in the same script or in a separate scripts.

To create the snapshot,

 New-Snapshot -VM (get-vm vmname) -Name nameyouchoose 

To delete the snapshot based on your criteria of 2 days,

 
$OldSnapshot = Get-VM vmname | get-snapshot | where {$_.Created -lt ((Get-Date).AddDays(-2))} 
Remove-Snapshot -Snapshot $OldSnapshot -confirm:$false

This should give you a starting point at least.

Chris Nakagaki (Zsoldier)

http://tech.zsoldier.com

[TomLon]

Lucd, that worked perfectly. I have no problem creating a script for each VM (as there is not that many for now), but is there a way to create an array of vms in a single script. That way, schedule it once for multiple VMs? Thanks

[LucD]

That's perfectly possible.

How would you provide the array of VMs ? In a CSV file for example ?

The CSV would have the following layout

vmName
vm1
vm2

Then you could do

$targetSnaps = 2

Import-Csv "C:\vm-names.csv" | %{

	$vm = Get-VM -Name $_.vmName

# Create daily snapshot
	$vm | New-Snapshot -Name ($_.vmName + " " + (Get-Date).ToShortDateString())

# Remove excess snapshots
	$snaps = $vm | Get-Snapshot | Sort-Object -Property Created -Descending
	if($snaps.Count -gt $targetSnaps){
		$targetSnaps..($snaps.Count - 1) | %{
			$snaps[$_] | Remove-Snapshot -Confirm:$false
		}
	}
}

____________

Blog: LucD notes

Twitter: lucd22

[WAMTech]

This looks great, a few more questions, where can I run it from and what extension will the script have? Thanks

[LucD]

You store the script in a .ps1 file and you can run it from the PowerCLI prompt.

____________

Blog: LucD notes

Twitter: lucd22

[WAMTech]

Great, I noticed you are one of the most active people in the powershell community, I really appreciate that, again I'm as green as it gets when it comes to powershell do you know any other resources I can tap into to get up to speed?

Thank you very much.

[LucD]

It's perhaps not too recent but in my My PS library post I listed some of the resources I use.

There is another book coming that delves into PowerCLI, see my PowerCLI Book Update post.

Jonathan, one of the co-authors, has a very good introductory post. See his 10 Steps to Kick-Start Your VMware Automation with PowerCLI post.

____________

Blog: LucD notes

Twitter: lucd22