Add command to force reset the state of RabbitMQ

This command can be invoked with ``kolla-ansible rabbitmq-reset-state``.
This is primarily designed to be used when enabling HA queues[1].

As such, this also updates the RabbitMQ documentation to use this
command.

[1] https://docs.openstack.org/kolla-ansible/latest/reference/message-queues/rabbitmq.html#high-availability

Change-Id: I6ad95a3618fc1a34af56657ef99ef14dc979f17a

ansible/rabbitmq-reset-state.yml

@@ -0,0 +1,10 @@
+---
+- name: Reset RabbitMQ state
+  hosts: rabbitmq
+  tasks:
+    - name: Include RabbitMQ reset-state tasks
+      include_role:
+        name: rabbitmq
+        tasks_from: reset-state
+      when:
+        - enable_rabbitmq | bool

ansible/roles/rabbitmq/tasks/reset-state.yml

@@ -0,0 +1,16 @@
+---
+- name: Stop the RabbitMQ application
+  become: true
+  command: "{{ kolla_container_engine }} exec rabbitmq rabbitmqctl stop_app"
+
+- name: Reset the state of RabbitMQ
+  become: true
+  command: "{{ kolla_container_engine }} exec rabbitmq rabbitmqctl force_reset"
+
+- name: Start the RabbitMQ application
+  become: true
+  command: "{{ kolla_container_engine }} exec rabbitmq rabbitmqctl start_app"
+
+- name: Wait for all RabbitMQ nodes to join the cluster
+  become: true
+  command: "{{ kolla_container_engine }} exec rabbitmq rabbitmqctl await_online_nodes {{ groups['rabbitmq'] | length }}"

doc/source/reference/message-queues/rabbitmq.rst

@@ -125,22 +125,32 @@ needed to migrate from transient to durable queues.
 1. Stop all OpenStack services which use RabbitMQ, so that they will not
    attempt to recreate any queues yet.
 
-2. Reconfigure RabbitMQ to enable classic queue mirroring.
+   .. code-block:: console
+
+      kolla-ansible stop --tags <service-tags>
+
+2. Generate the new config for all services.
 
    .. code-block:: console
 
-      kolla-ansible reconfigure --tags rabbitmq --skip-tags rabbitmq-ha-precheck
+      kolla-ansible genconfig
 
-3. Reset the state on each RabbitMQ node with the following commands. Each
-   command must be run on all RabbitMQ nodes before moving on to the next
-   command. This will remove all queues.
+3. Reconfigure RabbitMQ.
 
    .. code-block:: console
 
-      rabbitmqctl stop_app
-      rabbitmqctl force_reset
-      rabbitmqctl start_app
+      kolla-ansible reconfigure --tags rabbitmq
 
-4. Reconfigure the OpenStack services using ``kolla-ansible reconfigure``, at
-   which point they will start again and recreate the appropriate queues as
-   durable.
+4. Reset the state on each RabbitMQ, to remove the old transient queues and
+   exchanges.
+
+   .. code-block:: console
+
+      kolla-ansible rabbitmq-reset-state
+
+5. Start the OpenStack services again, at which point they will recreate the
+   appropriate queues as durable.
+
+   .. code-block:: console
+
+      kolla-ansible deploy --tags <service-tags>

releasenotes/notes/command-to-force-reset-rabbitmq-state-7ec4414fd2a63d16.yaml

@@ -0,0 +1,7 @@
+---
+features:
+  - |
+    The new command ``kolla-ansible rabbitmq-reset-state`` has been added. It
+    force-resets the state of RabbitMQ. This is primarily designed to be used
+    when enabling HA queues, see docs:
+    https://docs.openstack.org/kolla-ansible/latest/reference/message-queues/rabbitmq.html#high-availability

tools/kolla-ansible

@@ -193,6 +193,7 @@ Commands:
     gather-facts         Gather Ansible facts
     post-deploy          Do post deploy on deploy node
     pull                 Pull all images for containers (only pulls, no running container changes)
+    rabbitmq-reset-state Force reset the state of RabbitMQ
     reconfigure          Reconfigure OpenStack service
     stop                 Stop Kolla containers
     certificates         Generate self-signed certificate for TLS *For Development Only*
@@ -241,6 +242,7 @@ deploy-servers
 gather-facts
 post-deploy
 pull
+rabbitmq-reset-state
 reconfigure
 stop
 certificates
@@ -567,6 +569,10 @@ EOF
         ACTION="Cleanup disabled nova_libvirt containers"
         PLAYBOOK="${BASEDIR}/ansible/nova-libvirt-cleanup.yml"
         ;;
+(rabbitmq-reset-state)
+        ACTION="Force reset the state of RabbitMQ"
+        PLAYBOOK="${BASEDIR}/ansible/rabbitmq-reset-state.yml"
+        ;;
 (bash-completion)
         bash_completion
         exit 0