cluster_rabbitmq.yml

# ansible-playbook -i ec2.py cluster_rabbitmq.yml --limit tag_Name_stage-edx-commoncluster -e@/path/to/vars/env-deployment.yml -T 30 --list-hosts

- hosts: all
  become: True
  serial: 1
  vars:
    # By default take instances in and out of the elb(s) they
    # are attached to
    # To skip elb operations use "-e elb_pre_post=fase"
    elb_pre_post: true
    # Number of instances to operate on at a time
    serial_count: 1
  serial: "{{ serial_count }}"
  pre_tasks:
    - action: ec2_metadata_facts
    - debug:
        var: "{{ ansible_ec2_instance_id }}"
      when: elb_pre_post
    - name: Instance De-register
      local_action: ec2_elb
      args:
        instance_id: "{{ ansible_ec2_instance_id }}"
        region: us-east-1
        state: absent
        wait_timeout: 60
      become: False
      when: elb_pre_post
  tasks:
    - debug:
        var: "{{ ansible_ec2_local_ipv4 }}"
      with_items: "{{ list.results }}"
    - command: rabbitmqctl stop_app
    - command: rabbitmqctl join_cluster rabbit@ip-{{ hostvars.keys()[0]|replace('.', '-') }}
      when: hostvars.keys()[0] != ansible_ec2_local_ipv4
    - command: rabbitmqctl start_app
  post_tasks:
    - debug: var="{{ ansible_ec2_instance_id }}"
      when: elb_pre_post
    - name: Register instance in the elb
      local_action: ec2_elb
      args:
        instance_id: "{{ ansible_ec2_instance_id }}"
        ec2_elbs: "{{ ec2_elbs }}"
        region: us-east-1
        state: present
        wait_timeout: 60
      become: False
      when: elb_pre_post