Cannot create a Managed Agent Pool with ARM64 machines

[henning-krause]

I've created a virtual machine scale set in Azure using a Standard_D2ps_v5 machine on ARM64 using Ubuntu 22_04-lts-arm64.

Then I've created a Managed Agent Pool in Azure Devops.

When Azure Devops tries to scale the pool up to one from zero machines, I see this error message in the Activity log:

Title: Create or Update Virtual Machine Scale Set
Status: failed

In the details I see this under statusMessage:

{
  "status": "Failed",
  "error": {
    "code": "ResourceOperationFailure",
    "message": "The resource operation completed with terminal provisioning state 'Failed'.",
    "details": [
      {
        "code": "VMExtensionProvisioningError",
        "target": "2",
        "message": "VM has reported a failure when processing extension 'Microsoft.Azure.DevOps.Pipelines.Agent' (publisher 'Microsoft.VisualStudio.Services' and type 'TeamServicesAgentLinux'). Error message: 'The Extension failed to execute: The current CPU architecture is not supported. Deployment agent requires x64 architecture.'. More information on troubleshooting is available at https://aka.ms/vmextensionlinuxtroubleshoot. "
      }
    ]
  }
}

In #230. jgalliers said that he successfully created ARM based agents in the private preview.

Anything else I have to do here? Or isn't this supported right now?