Using PowerCLI to take snapshots and then removing snapshots

[jssidhu71]

Hi - Wonder if someone has a script to do the following:

Scenerio:

I have 400 Virtual Desktops within a cluster, i need to create a snapshot at the beginning of the week for 100 VMs, after 2 weeks, the snapshots for these 100 VMS will be removed reverting back to the original image.

Can this be done..? if so, can anyone assist please.

Thanks

[LucD]

How would these 100 VMs be selected out of the 400 you have ?

And is this a process that should be done every week, let's say on Monday ?

And did I understand correcly that once a snapshot is 2 weeks old, it can be removed ?

____________

Blog: LucD notes

Twitter: lucd22

[jssidhu71]

How would these 100 VMs be selected out of the 400 you have ?

--> A list would be supplied listing VM names

And is this a process that should be done every week, let's say on Monday ?

--> Yes, every other week

And did I understand correcly that once a snapshot is 2 weeks old, it can be removed ?

--> Yes, snapshot to be removed completely

[maishsk]

Throttling Snapshots

This can give you an idea of how to throttle the removal and how to create the snapshots

Maish - VCP - vExpert 2010

VMware Communities User Moderator

Virtualization Architect & Systems Administrator

Twitter - @maishsk

[LucD · Accepted solution]

This should do the trick

Import-Csv "C:\VMnames.csv" | %{
	Get-VM $_.Name | New-Snapshot -Name "Weekly snapshots" -Quiesce:$true -Confirm:$false
}
$twoweeksago = (Get-Date).AddDays(-14)
Get-VM | Get-Snapshot | %{
	if($_.Created.CompareTo($twoweeksago) -eq -1){
		Remove-Snapshot $_ -Confirm:$false
	}
}

The CSV file should look like this

Name
vm1
vm2
...

I assumed that the snapshot removal had to run over all 400 VMs.

If not the 2nd lookup has to be moved inside the Import-Csv loop.

You can schedule the script with Windows Scheduler.

Have a look at Alan's Running a PowerCLI Scheduled task post for the details.

____________

Blog: LucD notes

Twitter: lucd22

[jssidhu71]

Hey LucD.. many thanks for this..

how would the script look if i wanted to list a number of VMs to be snapshotted, then remove the snapshot back to the original image without the duration .. As i may have to snapshot a number of vms then remove the snapshot for the said vms..

Thanks Again !!

[LucD]

Not sure I understood that last question.

Do you want to take a snapshot and then immediatly remove it ?

____________

Blog: LucD notes

Twitter: lucd22

[jssidhu71]

Hey LucD..

I want to list a 100 VMS to create a snapshot leaving for a few days, i now want to list the same 100 VMS to remove the snapshot regardless of how long the snapshot has been taken.. basically snapshot a list of vms, then run a script listing vms to remove snapshot.

Thanks

[LucD]

That's quite easy.

To create the snapshots

Import-Csv "C:\VMnames.csv" | %{
     Get-VM $_.Name | New-Snapshot -Name "MySnapshot" -Quiesce:$true -Confirm:$false
}

To remove the snapshots

Import-Csv "C:\VMnames.csv" | %{
   Get-VM $_.Name | Get-Snapshot -Name "MySnapshot" | Remove-Snapshot -Confirm:$false
}

____________

Blog: LucD notes

Twitter: lucd22

[jssidhu71]

Many Thanks !!

[Parimal24]

Sorry to resurrect an old post. Thanks  LucD - with your script, I am able to take snapshots from CSV list perfectly, however, I am unable to commit/delete them when I run this code and get error:

Remove-Snapshot : Cannot bind parameter 'Snapshot'. Cannot convert the "@{Name=
SERVER1}" value of type "System.Management.Automation.PSCustomObject" to t
ype "VMware.VimAutomation.ViCore.Types.V1.VM.Snapshot".
At C:\Support\RemoveSnaps.ps1:2 char:96
+    Get-VM $_.Name | Get-Snapshot -Name "July Week 1 Patching CN000000099992"
| Remove-Snapshot <<<<  $_ -Confirm:$false
    + CategoryInfo          : InvalidArgument: (:) [Remove-Snapshot], Paramete
   rBindingException
    + FullyQualifiedErrorId : CannotConvertArgumentNoMessage,VMware.VimAutomat
   ion.ViCore.Cmdlets.Commands.RemoveSnapshot

Not sure what could be causing this? Can you decipher? I am running VCenter 4.1.0

[Parimal24]

Actually got it working by removing  $_ in the Remove-Snapshot cmdlet:

Import-Csv "C:\Support\Snapshotlist2.csv" | %{
   Get-VM $_.Name | Get-Snapshot -Name "July Week 1 Patching" | Remove-Snapshot -Confirm:$false
}

[LucD]

Yes, that was a typo. I corrected the code.

[orgazi]

Hi;

What if we put ip addresses of VMs instead of names of them into the csv file,then how would the script be changed?

Thank you.

[LucD]

It depends what the Displayname of the VMs are. Do they correspond with the hostname configured in the guest OS ?

If yes, the script would first need to read all the IP addresses from the CSV file.

Then do a name resolution, which would give the FQDN of the guest.

The first qualifier of the FQDN should be the same as the Displayname of the VM.

[orgazi]

Unfortunately display names and FQDN are not match in our env.

If it is better,we can put FQDNs in the csv file.

Actually the story is this:

Windows team gave me the list of vms' IPs and FQDNs,and want me to take snapshot them before patching.

[LucD]

Ip or FQDN is not the issue, we can easily convert between the two from within a PowerShell script.

Are the VMware Tools installed in each VM ?

If yes, we can use the FQDN to find the VM.

Something like this

$vmTab = @{}

# Set up hash table: key = FQDN

Get-VM | %{

    $vmTab.Add($_.Guest.HostName,$_)

}

# Loop through CSV, lookup VM on FQDN

Import-Csv vm.csv -UseCulture | %{

        Get-Snapshot -VM $vmTab[$_.fqdn]

}

[orgazi]

We got some error like:

Exception calling "Add" with "2" argument(s): "Key cannot be null.

Parameter name: key"

Our csv file goes like this:

test1,test2....

[LucD]

Was that by any chance for a VM that didn't have the VMware Tools installed ?

[orgazi]

Nope

both have vmtools running.