{"status":"Failed","error":{"code":"DeploymentFailed","target":"/subscriptions/.../resourceGroups/231000-azr/providers/Microsoft.Resources/deployments/vmss","message":"At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/arm-deployment-operations for usage details.","details":[{"code":"BadRequest","message":"Automatic OS Upgrade is not supported for this Virtual Machine Scale Set because a health probe or health extension was not specified."}]}}
I plan to add a probe for TCP on port 22 (SSH).