I have been spending a lot of time this week looking at all the functionality that is available in the Compare-VM PowerShell cmdlet in Hyper-V. The core concept of Compare-VM is that it returns a “virtual machine compatibility report” that lets you know about any problems that exist with the virtual machine.
Once you have the virtual machine compatibility report, you can fix the problems and then pass the report to the cmdlet that you actually wanted to use.
However, what if you are not sure that you have really fixed the problems with the virtual machine compatibility report? Simple – you can just pass the compatibility report back into Compare-VM.
This will recheck the virtual machine and let you know if there are any problems remaining. You can keep on doing this until you get a compatibility report with no incompatibilities. This is very handy if you are just messing around at the PowerShell prompt and want to double check yourself.