Creating a Custom Virtual Machine Image in Azure

Recently I needed to create a custom virtual machine (VM) image in Azure. The Azure Marketplace offers many different templates for operating system (OS) deployments, but sometimes there are situations where you may want to create your own custom image with specific changes to the OS or VM. In this blog post, I will demonstrate how to create a custom VM image.

Create a VM in the Azure portal and configure (for demo purposes I’m using Windows Server 2019 Datacenter)

Make any changes to customize the VM. In this specific instance I installed IIS and configured this VM to be a web server

Once you’ve completed customizing the VM, open Windows File Explorer (or use the command line) and browse to:

 C:\Windows\System32\Sysprep

Run the sysprep application

In the System Preparation Tool Window, select the following:
- Select ‘System Out-of-Box Experience (OOBE)’ from the System Cleanup Action dropdown
- Check the ‘Generalize’ checkbox
- Select ‘Shutdown’ from the Shutdown Options dropdown
- Click ‘OK’

Sysprep will process and shutdown the VM

In the Azure portal, open the Azure CLI and enter the following command to stop the VM

az vm stop --resource-group resource-group-name --name vm-name

This can also be done with Azure Powershell.

PS C:\> Stop-AzVM -ResourceGroupName "demo-rg" -Name "windows-vm"

On the VM properties page, click the ‘Capture’ button

On the ‘Create an Image’ flyout, complete the following:
- Enter image name
- Select or create a new resource group to save VM image in
- Check ‘Automatically delete this virtual machine after creating the image’
- Enter VM Name
- Click ‘Create’ at the bottom of the screen