Azure ARM: Shared Images and Managed Images

I feel like I am doing something wrong here but I’m not sure what.

I have created a shared image gallery, and a few shared images with Terraform, and am using Packer to create shared image versions.

In packer I have the following defined:

  • managed_image_name : The name matching the shared image I created with Terraform (
  • shared_image_gallery_destination.image_name : Same as above
  • shared_image_gallery_destination.version: Some number I increment with each build, e.g. 18.4.1

Whenever I increment the version and build a new image I have to use -force because of the following error:

Build ‘azure-arm’ errored: the managed image named Concourse already exists in the resource group packer, use the -force option to automatically delete it.

Am I doing something misguided here, or is that the expected behavior with shared image versions?