Reverting to a specific snapshot

[jfierberg]

get-vm $servername | get-snapshot

When I execute this cmdlet I get the listing of the snapshots for the specific vm. I want to know how to select one of the snapshots and revert back to it. The example in the hand's on lab PDF does not show how this is done.

[admin]

Try get-vm $servername | get-snapshot $snapshotname | set-vm -vm (get-vm $servername)

[jfierberg]

Thanks but that did not work. I tried the code below also and it failed.

get-vm $servername | get-snapshot | foreach { `

$_.VM | set-vm -snapshot $snapshotname `

-confirm:$false `

}

[admin]

Well, selecting the snapshot is your algorithm. As Carter suggested, it could be something like a known name. If that is the case, then I'll offer a minor tweak on Carter's code:

get-vm $servername | get-snapshot -name LastKnownGood | % { set-vm -vm $_.vm -snapshot $_ }

If your algorithm for selecting the snapshot is more involved, then it becomes something like:

$snapshotList = get-vm $servername | get-snapshot
# whatever logic you want to apply here, whether it's selecting by date created or by description or by ordinal number or...
# and of course checking for an empty list...
$snapshotToUse = {logic here}
set-vm -vm $snapshotToUse.vm -snapshot $snapshotToUse

[jfierberg]

get-snapshot | where ......

Is there a way to determine what the property names are for the snapshots?

[admin]

get-snapshot | where ......

Is there a way to determine what the property names are for the snapshots?

Try get-vm | get-snapshot | get-member

[halr9000]

get-vm $servername | get-snapshot | foreach { `

$_.VM | set-vm -snapshot $snapshotname `

-confirm:$false `

}

PowerShell tip: (and I need to find or make good documentation on this) line termination and continuation characters are not required that often.

• An open brace { , parenthesis ( , or square bracket [ will allow for continuation across multiple lines until the block is closed by the corresponding } ) ]

• A trailing comma (the array operator) will allow for a line break until the next array member

• Single and double-quotes will work as well, but I really don't recommend doing so just because its unexpected and confusing to read the code.

So you can do this without a single line-continuation character (a trailing back-tick ` )

function test {
  param (
    $firstname,
    $lastname
  )
  (get-process) [
    1
  ]
  write-host "$firstname
$lastname"
}

Hal Rottenberg

Co-Host, PowerScripting Podcast (http://powerscripting.net)

[jfierberg]

I was able to select a specific snapshot using the following code:Get-VM $servername | Get-Snapshot | where { $_.name -like $snapshotname}

If I add at the end of the statement | set-vm -snapshot $_, I get "the input object cannot be bound to any parameters for the command either because the command does not take pipeline input..."

[admin · Accepted solution]

I was able to select a specific snapshot using the following code:Get-VM $servername | Get-Snapshot | where { $_.name -like $snapshotname}

If I add at the end of the statement | set-vm -snapshot $_, I get "the input object cannot be bound to any parameters for the command either because the command does not take pipeline input..."

Since you're piping the snapshot in to set-vm, you don't need the -snapshot argument, but you do need the -vm argument. You can either tweak that in this way:

get-vm $servername | get-snapshot | where { $_.name -like $snapshotname } | set-vm -vm (get-vm $servername)

Or, you could do it Antonio's way, which is more efficient:

get-vm $servername | get-snapshot | where { $_.name -like $snapshotname } | % { set-vm -vm $_.vm -snapshot $_ }

[jfierberg]

Thank you very much. That worked like a champ.