These days, I give a lot of presentations and demos on Windows Server 2012. Of course, many involve Hyper-V related demos. Although I run most demos from PowerShell, since now I can, I modify a lot in my demo environment. And since I frequently use my environment I need to be able to prepare my start my environment, prepare it, run the demos, revert to the state it was in when I started and finally shut down my environment.
At least the start, preparation (including tests), reverting and shutting down are all done using PowerShell scripts. Sometimes I have only 15 minutes to connect my machines to power and network. In that time, I don’t have time to manually start everything and use a document to follow what needs to be done. And what about some basic tests to verify everything is working correctly?
Think about it: starting the machines, waiting until they are alive, connecting through RDP to some of them and some virtual machines, starting VMconnect sessions, starting Hyper-V Manager, Server Manager, PowerShell console, configuring networks, etc, etc. Quite easy to forget some steps and hit issues during demos.
I normally don’t connect my presentation machine to the external monitor (large screen, beamer, etc.) until the environment is ready. But to show the power of automation, I did show a technical audience once how I start my environment (up to the point when it is ready). People were obviously impressed with the amount of automation I used.
Last month I presented at a large Microsoft event and got some questions from colleagues as well on how I started my machines without touching them. The script used Wake On LAN, something most machines support these days and which is on most of them on by default. I simply connect my machines to my switch and turn them on from my presentation machine.
In this post, I share my script for others to use. The script follows some PowerShell best practices:
· The name of the script is in the Verb-Noun form.
· The script is documented with comment based help.
The only thing you need to get it to work is the Wake On LAN tool. Other than that, you should be able to use it right away, once you have created the CSV file with machine names.
So how does it work?
The script uses a CSV file with machines you want to wake up. It starts with the first and works its way down the list. Not only does it wake the machines, it also sends echo requests to verify IP connectivity. It continues to send requests (number configurable) and then goes on to the next machine with wake up. I have developed a progress bar which displays progress on the wake up, the echo request and remaining phase of sending/receiving echo requests/replies.
You can download the script, tool and sample machine.csv here.
Update, June 3rd 2012
I have updated my script to be able to do without the wolcmd tool. As pointed out in the comments, it is possible to do this from within PowerShell. So I did some research in MSDN and rewrote my script.
The switches have changed as well. You can now provide the time out, repeat and number of magic packets to send. Run Get-Help .\WakeUp-Machines.ps1 to get additional help (-detailed, –examples, –full all supported).