I don’t think I’m the one today that has to convince you that backing up Virtual Machines in Azure is really simple. A few weeks ago, things even got more simplified, with the backup functionality placed right into the context menu of Virtual Machines in Azure.  This all works great for VM’s created from images found in the gallery, but what about Virtual Machines

When you’re deploying a Virtual Machine in Azure from the Azure gallery, using the portal or PowerShell, one of the things that is always installed, is a VM Agent. The VM Agent is a light weight process intended to piggy-back additional solutions, offered both by Microsoft and partners, for configuring, managing, and accelerating Virtual Machines. One of the features powered by this agent is the Backup Extension.

Although very much needed in the Virtual Machine, the agent doesn’t show up in the “Programs and Features” menu, it’s installed to ed to C:\WindowsAzure and extensions are installed in C:\Packages. If you want to check the version of the agent, in combination with Azure Backup, you should find the WaAppAgent.exe file in the Packages folder. Right-click the file, go to Properties, and then select the Details tab. The Product Version field should be 2.6.1198.718 or higher.

When installed, there are three services/processes relevant to the agent:

  • RdAgent service (WaAppAgent.exe)

  • WindowsAzureGuestAgent service (WindowsAzureGuestAgent.exe)

  • WindowsAzureTelemetryService service (WindowsAzureTelemetryService.exe)

Using a custom image deployment

Again, this is all great when using “standard” images, which are provisioned through the Azure Marketplace, but how do I get this to work on my custom Windows image? Well, turns out, it’s not that difficult..

Step 1 is to get your hands on the VM Agent installer, which can be found here.

In Step 2, install the agent, inside the Virtual Machine with an account which has administrative privileges on that VM.

Once the VM Agent is installed on the virtual machine, the Azure Backup service installs (piggy-backs) the backup extension to the VM Agent. The Azure Backup service seamlessly upgrades and patches the backup extension without additional user intervention.

The backup extension is installed by the Backup service whether the VM is running. A running VM provides the greatest chance of getting an application-consistent recovery point. However, the Azure Backup service continues to back up the VM even if it is turned off, and the extension could not be installed. This is known as Offline VM. In this case, the recovery point will be crash consistent.

In this post I’ve covered how you can still enable VM Backups for your custom images used in Azure. For reference, I’ve provided two links to related information below.

Managing VM Extensions

Protecting VM’s with Azure Backup

Want to know more, or did any questions come up when you were reading this?
Do you have some feedback for me? Leave a comment or drop me an email.

Until the next time, keep it cloudy!

Bert Wolters

Leave a Reply