Copy snapshot of a managed disk to same or different subscription with CLI

This article contains two scripts. The first script copies a snapshot of a managed disk that was using platform-managed keys to the same or a different subscription. The second script copies a snapshot of a managed disk that was using customer-managed keys to the same or a different subscription. These scripts can be used for the following scenarios:

  • Migrate a snapshot in Premium storage (Premium_LRS) to Standard storage (Standard_LRS or Standard_ZRS) to reduce your cost.
  • Migrate a snapshot from locally redundant storage (Premium_LRS, Standard_LRS) to zone redundant storage (Standard_ZRS) to benefit from the higher reliability of ZRS storage.
  • Move a snapshot to different subscription in the same region for longer retention.

Note

Both subscriptions must be located under the same tenant

If you don't have an Azure subscription, create an Azure free account before you begin.

Prerequisites

Sample script

Launch Azure Cloud Shell

The Azure Cloud Shell is a free interactive shell that you can use to run the steps in this article. It has common Azure tools preinstalled and configured to use with your account.

To open the Cloud Shell, just select Try it from the upper right corner of a code block. You can also launch Cloud Shell in a separate browser tab by going to https://shell.azure.com.

When Cloud Shell opens, verify that Bash is selected for your environment. Subsequent sessions will use Azure CLI in a Bash environment, Select Copy to copy the blocks of code, paste it into the Cloud Shell, and press Enter to run it.

Sign in to Azure

Cloud Shell is automatically authenticated under the initial account signed-in with. Use the following script to sign in using a different subscription, replacing <Subscription ID> with your Azure Subscription ID. If you don't have an Azure subscription, create an Azure free account before you begin.

subscription="<subscriptionId>" # add subscription here

az account set -s $subscription # ...or use 'az login'

For more information, see set active subscription or log in interactively

Disks with platform-managed keys

#Provide the subscription Id of the subscription where snapshot exists
sourceSubscriptionId="<subscriptionId>"

#Provide the name of your resource group where snapshot exists
sourceResourceGroupName=mySourceResourceGroupName

#Provide the name of the snapshot
snapshotName=mySnapshotName

#Set the context to the subscription Id where snapshot exists
az account set --subscription $sourceSubscriptionId

#Get the snapshot Id 
snapshotId=$(az snapshot show --name $snapshotName --resource-group $sourceResourceGroupName --query [id] -o tsv)

#If snapshotId is blank then it means that snapshot does not exist.
echo 'source snapshot Id is: ' $snapshotId

#Provide the subscription Id of the subscription where snapshot will be copied to
#If snapshot is copied to the same subscription then you can skip this step
targetSubscriptionId=6492b1f7-f219-446b-b509-314e17e1efb0

#Name of the resource group where snapshot will be copied to
targetResourceGroupName=mytargetResourceGroupName

#Set the context to the subscription Id where snapshot will be copied to
#If snapshot is copied to the same subscription then you can skip this step
az account set --subscription $targetSubscriptionId

#Copy snapshot to different subscription using the snapshot Id
#We recommend you to store your snapshots in Standard storage to reduce cost. Please use Standard_ZRS in regions where zone redundant storage (ZRS) is available, otherwise use Standard_LRS
#Please check out the availability of ZRS here: https://docs.microsoft.com/en-us/azure/storage/common/storage-redundancy-zrs#support-coverage-and-regional-availability
az snapshot create --resource-group $targetResourceGroupName --name $snapshotName --source $snapshotId --sku Standard_LRS

Disks with customer-managed keys

#Provide the subscription Id of the subscription where snapshot exists
sourceSubscriptionId="<subscriptionId>"

#Provide the name of your resource group where snapshot exists
sourceResourceGroupName=mySourceResourceGroupName

#Provide the name of the target disk encryption set
diskEncryptionSetName=myName

#Provide the target disk encryption set resource group
diskEncryptionResourceGroup=myGroup

#Provide the name of the snapshot
snapshotName=mySnapshotName

#Set the context to the subscription Id where snapshot exists
az account set --subscription $sourceSubscriptionId

#Get the snapshot Id 
snapshotId=$(az snapshot show --name $snapshotName --resource-group $sourceResourceGroupName --query [id] -o tsv)

#If snapshotId is blank then it means that snapshot does not exist.
echo 'source snapshot Id is: ' $snapshotId

#Get the disk encryption set ID
diskEncryptionSetId=$(az disk-encryption-set show --name $diskEncryptionSetName --resource-group $diskEncryptionResourceGroup)

#Provide the subscription Id of the subscription where snapshot will be copied to
#If snapshot is copied to the same subscription then you can skip this step
targetSubscriptionId=6492b1f7-f219-446b-b509-314e17e1efb0

#Name of the resource group where snapshot will be copied to
targetResourceGroupName=mytargetResourceGroupName

#Set the context to the subscription Id where snapshot will be copied to
#If snapshot is copied to the same subscription then you can skip this step
az account set --subscription $targetSubscriptionId

#Copy snapshot to different subscription using the snapshot Id
#We recommend you to store your snapshots in Standard storage to reduce cost. Please use Standard_ZRS in regions where zone redundant storage (ZRS) is available, otherwise use Standard_LRS
#Please check out the availability of ZRS here: https://docs.microsoft.com/en-us/azure/storage/common/storage-redundancy-zrs#support-coverage-and-regional-availability
#To change the region, use the --location parameter
az snapshot create -g $targetResourceGroupName -n $snapshotName --source $snapshotId --disk-encryption-set $diskEncryptionSetID --sku Standard_LRS --encryption-type EncryptionAtRestWithCustomerKey

Clean up resources

Run the following command to remove the resource group, VM, and all related resources.

az group delete --name mySourceResourceGroupName

Sample reference

This script uses following commands to create a snapshot in the target subscription using the Id of the source snapshot. Each command in the table links to command specific documentation.

Command Notes
az snapshot show Gets all the properties of a snapshot using the name and resource group properties of the snapshot. The Id property is used to copy the snapshot to different subscription.
az snapshot create Copies a snapshot by creating a snapshot in different subscription using the Id and name of the parent snapshot.

Next steps

Create a virtual machine from a snapshot

For more information on the Azure CLI, see Azure CLI documentation.

More virtual machine and managed disks CLI script samples can be found in the Azure Linux VM documentation.