kubeasz/playbooks/21.addetcd.yml

# add new-etcd node, one at a time
- hosts: "{{ NODE_TO_ADD }}"
  tasks:
  # step1: find a healthy member in the etcd cluster
  - block:
    - name: set NODE_IPS of the etcd cluster
      set_fact: NODE_IPS="{% for host in groups['etcd'] %}{{ host }} {% endfor %}"

    - name: get etcd cluster status
      shell: 'for ip in {{ NODE_IPS }};do \
                ETCDCTL_API=3 {{ base_dir }}/bin/etcdctl \
                --endpoints=https://"$ip":2379 \
                --cacert={{ cluster_dir }}/ssl/ca.pem \
                --cert={{ cluster_dir }}/ssl/etcd.pem \
                --key={{ cluster_dir }}/ssl/etcd-key.pem \
                endpoint health; \
              done'
      register: ETCD_CLUSTER_STATUS

    - debug: var="ETCD_CLUSTER_STATUS"

    - name: get a running ectd node
      shell: 'echo -e "{{ ETCD_CLUSTER_STATUS.stdout }}" \
               "{{ ETCD_CLUSTER_STATUS.stderr }}" \
               |grep "is healthy"|sed -n "1p"|cut -d: -f2|cut -d/ -f3'
      register: RUNNING_NODE

    - debug: var="RUNNING_NODE.stdout"
    connection: local

  # step2: add a new member in the etcd cluster
  - name: add a new etcd member
    shell: "ETCDCTL_API=3 {{ bin_dir }}/etcdctl member add etcd-{{ NODE_TO_ADD }} \
            --peer-urls=https://{{ NODE_TO_ADD }}:2380"
    delegate_to: "{{ RUNNING_NODE.stdout }}"

# step3: start the new-etcd node
- hosts: "{{ NODE_TO_ADD }}"
  vars:
    CLUSTER_STATE: existing
  roles:
  - { role: os-harden, when: "OS_HARDEN|bool" }
  - { role: chrony, when: "groups['chrony']|length > 0" }
  - prepare
  - etcd