kubespray/roles/etcd/tasks/configure.yml

---
- name: Configure | Check if member is in cluster
  shell: "{{ bin_dir }}/etcdctl --no-sync --endpoints={{ etcd_access_addresses }} member list | grep -q {{ etcd_access_address }}"
  register: etcd_member_in_cluster
  ignore_errors: true
  changed_when: false
  check_mode: no
  when: is_etcd_master
  tags:
    - facts
  environment:
    ETCDCTL_CERT_FILE: "{{ etcd_cert_dir }}/node-{{ inventory_hostname }}.pem"
    ETCDCTL_KEY_FILE: "{{ etcd_cert_dir }}/node-{{ inventory_hostname }}-key.pem"

- name: Install etcd launch script
  template:
    src: etcd.j2
    dest: "{{ bin_dir }}/etcd"
    owner: 'root'
    mode: 0755
    backup: yes
  notify: restart etcd

- name: Configure | Copy etcd.service systemd file
  template:
    src: "etcd-{{ etcd_deployment_type }}.service.j2"
    dest: /etc/systemd/system/etcd.service
    backup: yes
  when: is_etcd_master
  notify: restart etcd

- name: Configure | Join member(s) to cluster one at a time
  include_tasks: join_member.yml
  vars:
    target_node: "{{ item }}"
  loop_control:
    pause: 10
  with_items: "{{ groups['etcd'] }}"
  when: inventory_hostname == item and etcd_member_in_cluster.rc != 0 and etcd_cluster_is_healthy.rc == 0