Comment 1 for bug 1489947

The instance I've seen of this error was a downstream problem, caused by an SSH error in the heat_api container.

The problem is that the stack_user_domain_id variable is set as part of the heat_domain_setup role, which runs only for the first heat container in the group, normally the one for heat-api. If for whatever reason this container bad, the variable will not get registered.

Then the heat_post_install task runs for all heat containers, and expect this variable to be set, causing this error.

I recommend that we drop the use of the stack_user_domain_id variable and instead specify the domain by name using stack_user_domain_name. Either one of these vars can be specified in the heat config. See https://github.com/openstack/heat/blob/27525fb0e446ff36e94c8eff0c93af473e67a3e2/heat/common/config.py#L64-L73.

Jesse, feel free to assign to me if you want me to make this change.