---
upgrade:
  - |
    RabbitMQ replica count has changed from n to (n//2+1) where n is the number
    of RabbitMQ nodes. That is, for a 3 node clusters, we request exactly 2
    replicas, for a 1 node cluster, we request 1 replica, and for a 5 node
    cluster, we request 3 replicas. This only has an effect if
    `om_enable_rabbitmq_high_availability` is set to `True`, otherwise queues
    are not replicated. The number of mirrored queues is not changed
    automatically, and instead requires the queues to be recreated (for
    example, by restarting RabbitMQ).
    This follows the good practice advice here:
    https://www.rabbitmq.com/ha.html#replication-factor
    A major motivation is to reduce the load on RabbitMQ in larger
    deployments. It is hoped, the improved performance should also
    help rabbitmq recover more quickly from cluster issues.
    Note that the contents of the RabbitMQ definitions.json are now changed,
    meaning RabbitMQ containers will be restarted on next deploy/upgrade.