Deploy a ARM VM using an existing VHD in Azure

Another day, one of my costumer wants to rebuild a virtual machine from the existing VHD and place on the new Resource Group and on a different VLAN, but without transferring VHD. The idea was to park the VHD on a storage account to avoid transferring this huge VHD.

First, I want to clarify if you delete the VM, you are not deleting the all the resources, that means that the vhd(s), network adapter9s) or the network IPs will remain intact. You are only deleting the compute section of the VM. That means you can redeploy using the same configuration, or change the network, for example.

To achieve that though, you need to do it through PowerShell and/or using JSON files.

So, if you change the original JSON file just replacing the VHD you will probably get an error message saying, “Cannot attach an existing OS disk if the VM is created from a platform or user image.

To avoid that you have to change the JSON file to reflect createOption to use the attach method instead.

Here is what you need to change:

Original JSON:

“storageProfile”: {

“imageReference”: {

“publisher”: “MicrosoftWindowsServer”,

“offer”: “WindowsServer”,

“sku”: “[parameters(‘windowsOSVersion’)]”,

“version”: “latest” },

“osDisk”: { “createOption”: “FromImage” },


Replace with:

“storageProfile”: {

“osDisk”: { “createOption”: “attach”,

“managedDisk”: {

“id”: [Managed_Disk_ID] },





Marcos Nogueira
Azure MVP
Twitter: @mdnoga

Marcos Nogueira

With more than 18 years experience in Datacenter Architectures, Marcos Nogueira is currently working as a Principal Cloud Solution Architect. He is an expert in Private and Hybrid Cloud, with a focus on Microsoft Azure, Virtualization and System Center. He has worked in several industries, including Aerospace, Transportation, Energy, Manufacturing, Financial Services, Government, Health Care, Telecoms, IT Services, and Gas & Oil in different countries and continents. Marcos was a Canadian MVP in System Center Cloud & Datacenter Managenment and he has +14 years as Microsoft Certified, with more than 100+ certifications (MCT, MCSE, and MCITP, among others). Marcos is also certified in VMware, CompTIA and ITIL v3. He assisted Microsoft in the development of workshops and special events on Private & Hybrid Cloud, Azure, System Center, Windows Server, Hyper-V and as a speaker at several Microsoft TechEd/Ignite and communities events around the world.

One Reply to “Deploy a ARM VM using an existing VHD in Azure”

Leave a Reply

Your email address will not be published. Required fields are marked *