Add/remove users only on the master node in the cluster

[aignas]

Hi @jasonroyle,

Thanks a lot for this ansible role. I found this to be the best thing available at the moment for creation of a new RabbitMQ cluster. However, I stumbled upon a few problems. One of them was user creation and deletion.

When ensuring that the users are rabbitmq users absent, we should not fail if they are not there. I think that this may be a bug in the rabbitmq_user directive in ansible itself, or the version of ansible I am using. I will investigate this more later, but thought I would let you know.

However, I had problems with user creation with this role. I noticed, that when creating new users, if I run it against all hosts in the cluster, then it fails randomly on different hosts. I believe that this is due to the fact that the user configuration is shared across all of the nodes in the cluster and we only need to run the user management tasks only on the master node.

See different ansible rabbitmq role where the rabbitmq.yml tasks are run only on the master if the cluster is being created and this is where all of the user management is done.

At the moment I have worked around the issue by copying the task locally and having the extra constraints, but it would be nice to fix it here.

All the best,
Ignas