Kubernetes RabbitMQ queue mirroring

Add a definitions.json file into your ConfigMap and ensure that your pods mount the file (in /etc/rabbitmq). In that file, specify all exchanges/queues, and have a policy defined for mirroring that would be applied to those exchanges/queues.

It may be easier to manually set this up and export the definitions file from a running RabbitMQ node.

This way - your cluster is all configured when started.

You can enable RabbitMQ mirroring using Kubernetes lifecycle.

The following entry is how I did it. It's not perfect on openshift the first pod of the statefulset restart once at launch.

    lifecycle:      postStart:        exec:          command:            - "/bin/bash"            - "-c"            - "for i in $(seq 15 -1 1); do sleep 2; done; until rabbitmqctl status; do sleep 2; done; rabbitmqctl set_policy ha \".\" '{\"ha-mode\":\"exactly\", \"ha-params\":2, \"ha-sync-mode\":\"automatic\"}'"

The first loop is to wait for node to configure itself or it would interact with a temporary configuration. The second is the wait the start of the RabbitMQ.

This configuration will enable duplicating all queue with two replicas.

Also keep in mind that if the postStart failed the container will failed too. Also using a postStart will delay the readiness of the pod till the postStart command return.