Sometime between July 12th – our last successful Azure VM agent for Jenkins – and September 12th, the deployments of new agents from Jenkins stopped working. I upgraded to 1.2.1 today and tested it, and the deployment failed with the following error:

{"code":"DeploymentFailed","message":"At least one resource deployment operation failed. Please list deployment operations for details. Please see https://aka.ms/arm-debug for usage details.","details":[{"code":"BadRequest","message":"{\r\n \"error\": {\r\n \"code\": \"InvalidParameter\",\r\n \"message\": \"Required parameter 'hyperVGeneration' is missing (null).\",\r\n \"target\": \"hyperVGeneration\"\r\n }\r\n}"}]}

I tried downgrading to 1.2.0 in case that was the issue, but it has the same issue – suggesting that this is a new requirement on the Azure side that the Azure VM Agents plugin is not handling.

This entirely blocks the usage of Azure agents, so we have no workaround but to use permanent agents or alternate clouds.