Manage VMware snapshots with PowerCLI

Manually taking a snapshot under VMware is easy : connect to the HTML5 Web UI, find the server from the list, right click, select Snapshot, Name it… However, when you have to do it several times in a row, it becomes really frustrating. Let’s see how to improve that.

Here comes PowerCLI

VMware released an awesome (and I am Linux guy) tool to manage your virtual machines from the command line. It is called PowerCLI, is based on PowerShell and honestly it really works like a charm.

it can be installed on Windows, Linux, Macos and of course inside a Docker container. I’ll let the installation part up to you, there is plenty of guides available on internet, but I’ll share my scripts.

My current workflow

I often change / refine / try to improve my workflow. However, for current workflow for managing updates on our Linux servers is like below :

• Make a snapshot of every server with PowerCLI, and give them a relevant name ;
• Apply update with Ansible (and reboot them if required) ;
• Delete snapshots after 2 days if everything is OK.

With no further ado, here are my scripts :

Create snapshots :

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Connect-VIServer -server vcenter.domain.com $vmlist = "srv-1", "srv-2", "srv-3" foreach($VM in $VMlist) { New-Snapshot -VM $vm -Name Before_Update -confirm:$false -runasync:$true } Disconnect-VIServer -Confirm:$false

Delete snapshots :

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Connect-VIServer -server vcenter.domain.com $vmlist = "srv-1", "srv-2", "srv-3" foreach($VM in $VMlist) { Get-Snapshot -VM $vm | where {$_.Name -match "Before_Update"} | Remove-Snapshot -RunAsync -Confirm:$False } Disconnect-VIServer -Confirm:$false

Let me walk you through what it does.

• First line, connects to the VMware server and will pompt for credentials.
• Then I declare an array or server, simply replace and add as many servers as you like.
• Simple foreach loop, goes through every server of the above defined array and does its job. Make sure to check official docs for more info about extra flags.
• NB : I use a relevant name, here “Before_Update” for my snapshots. It makes it easier to manage them since I know their name.
• Finally, we disconnect from the server.

I hope those little scripts will make you life a little easier, and hopefully your job a little less boring. Automating is the way to go!