One confusion around all of our extensions is: how are reboots handled? This varies by extension, but only VM Applications provide the option on how to handle them. It does this via the "scriptBehaviorAfterReboot" property.     "resources": [         {             "type": "Microsoft.Compute/galleries/applications/versions",             "apiVe...

One confusing area regarding extensions on Azure VMs is - what happens when the OS disk is swapped out? Well, in that case the extensions will run again. Is this the desired behavior? Well, we don't know. There are many types of extensions. Some handle monitoring and security, so those you'll probably want to keep. Some install applications, lik...

Today, all scripts run through Managed RunCommand will by default use Powershell 5. What if you have a script that requires Powershell7? This is supported via a new feature, but you will need to specify the different script shell. Here's what you need to do. Ensure your VM has Powershell7 Powershell7 is not installed by default. To ensure ...

For those familiar with the JsonAdDomain extension, it provides an easy way to join VMs to your domain. However, one aspect that customers have been less crazy about is that the domain password must be shared in the protected settings (where it is at least encrypted) and, more importantly, the functionality of the extension doesn't work well with s...

One great advantage of VM Applications is the ability to specify how many replicas you want for each VM Application version. While documentation exists on how to specify replicas, we don't really provide advice on determining how many replicas to use. The goal of this post is to rectify that gap. First, the basics. When you specify a replica cou...

As most of you may know from the current Managed RunCommand documentation there are multiple ways your script may be specified. However, what if your script uses various artifacts that also must be downloaded to the machine? Well, in the past it was necessary to call RunCommand are use some other technique to get those files on the...

Perhaps one of the largest differences between "Action RunCommand" (internally called RunCommand V1) and "Managed RunCommand" (internally called RunCommand V2) is that Managed RunCommands are ARM resources themselves. That means you can use them in ARM templates. Recently, I needed to issue a RunCommand in an ARM template, so I looked around for...

One of the lesser known differences between RunCommand and CustomScriptExtension is the fact that we do promise to not re-run your script in RunCommand, but no such promise exists for CustomScript. This is mentioned in the documentation, which isn't often fully understood. However, more than once I've been asked: when does CSE actually re-...

In both VmApplications and RunCommand, we support a property called "treatFailureAsDeploymentFailure". Note that for Managed RunCommand it may not be visible yet in Powershell or CLI, but it is available via ARM. Note that this flag is only available for managed RunCommand. It is not available for action RunCommand. For those unaware, managed RunCo...

I admit that VM Application names can be a bit tricky, or at least non-intuitive. The basic issue is this, you have some binary - let's call it MyApp.exe - and you want to install it on your VM. Therefore, you create a blob with the name MyBlob and set your install script to the following: You then name your VM Application "MyVmApp" and d...