Troubleshoot the AvailabilityZoneNotSupported error code

This article discusses how to identify and resolve the "AvailabilityZoneNotSupported" error that occurs when you try to create an Azure Kubernetes Service (AKS) cluster.

Prerequisites

Access to Azure CLI.

Symptoms

An AKS cluster creation fails in specified availability zones, and you receive an "AvailabilityZoneNotSupported" error with the following message:

Preflight validation check for resource(s) for container service <resource-name> in resource group <resource-group-name> failed. Message: The zone(s) '1' for resource '<agentpoolName>' is not supported. The supported zones for location '<location>' are 'A', 'B'

Cause

The issue occurs because the requested SKU has restrictions in some or all zones of your subscription. To verify the restrictions, go to the Verify SKU restrictions section.

Solution

To resolve this issue, follow the Azure region access request process to request access to the specified region or zone.

Verify SKU restrictions

1. List the SKU details by running one of the following commands:

   az vm list-skus -l <location> --size <SKU> 
   

   az rest --method get \
       --url "https://management.azure.com/subscriptions/<subscription>/providers/Microsoft.Compute/skus?%24filter=location+eq+%27<location>%27&api-version=2022-03-01"  >> availableSkus.txt
   

   Note

   Replace <subscription>, <SKU>, and <location> accordingly.

2. Search for the requested SKU from the command output.

3. If you see information like the following, it indicates that the requested SKU has restrictions in some or all zones of your subscription:

   "restrictions": [
                   {
                       "type": "Zone",
                       "values": [
                           "<zone>"
                       ],
                       "restrictionInfo": {
                           "locations": [
                               "<location>"
                           ],
                           "zones": [
                               "1",
                               "2",
                               "3"
                           ]
                       },
                       "reasonCode": "NotAvailableForSubscription"
                   }
               ]
   

Contact us for help

If you have questions, you can ask Azure community support. You can also submit product feedback to Azure feedback community.