An Ansible playbook that changes the name of a mongo replication set

rename-replset.yml

# Renames a mongo replication set
# This necessarily resyncs the secondaries, taking them offline, but total downtime on the primary should be short.
#
# Usage:
#  ansible-playbook rename_replset.yml -e 'password=SuperSecretAdminPassword name=new_replset_name' -i host1,host2,host3
#
# Note: the first host in the specified inventory will become the new primary

- hosts: all
  vars:
    password: null
    name: null
    replset_config:
      - "replication:"
      - "\\s+replSetName:.*"

  tasks:
    - fail: '{{ item }} must be set. Pass it with "-e {{ item }}=value"'
      when: item is none
      with_items:
        - password
        - name

    - name: Remove replset config
      become: true
      replace:
        dest: /etc/mongod.conf
        regexp: "^({{ item }})"
        replace: "#\\1"
      with_items: replset_config

    - name: Restart mongod
      become: true
      service:
        name: mongod
        state: restarted

    # The "local" database stores the replset config. We've got to wipe it out to make a new replset.
    - name: Drop local replset config
      shell: >
       /usr/bin/mongo -u admin -p {{ password }} --authenticationDatabase admin local
       --eval 'printjson(db.dropDatabase())'

    - name: Switch to new replset name
      become: true
      replace:
        dest: /etc/mongod.conf
        regexp: "(^#\\s+replSetName:)(.*)"
        replace: "\\1 {{ name }}"

    - name: Re-add replset config
      become: true
      replace:
        dest: /etc/mongod.conf
        regexp: "^#({{ item }})"
        replace: "\\1"
      with_items: replset_config

    - name: Restart mongod
      become: true
      service:
        name: mongod
        state: restarted

    - name: Initialize replica set
      run_once: true
      delegate_to: "{{ play_hosts[0] }}"
      shell: >
        /usr/bin/mongo -u admin -p {{ password }} admin --eval 'printjson(rs.initiate())'

    - name: Format secondaries
      run_once: true
      local_action:
        module: debug
        msg: '"{{ item }}:27017"'
      with_items: play_hosts[1:]
      register: secondaries

    - name: Add secondaries
      run_once: true
      delegate_to: "{{ play_hosts[0] }}"
      shell: >
        /usr/bin/mongo -u admin -p {{ password }} admin --eval 'printjson(rs.add({{ item.msg }}))'
      with_items: secondaries.results

Hi..I see below error when I use these last three tasks

TASK [mongodb-setup : Add secondaries] *******************************
fatal: [host1]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'ansible.utils.unsafe_proxy.AnsibleUnsafeText object' has no attribute 'msg'\n\nThe error appears to have been in '/var/lib/awx/projects/_dev/roles/mongodb-setup/tasks/users.yml': line 15, column 3, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n\n- name: Add secondaries\n  ^ here\n"}
mong

I last used this playbook in October 2015. Since then Ansible and possibly MongoDB have evolved significantly, so it's more than likely that this playbook no longer works. Pull requests welcome!