如何使用 ansible 在 docker 中运行 etcd 集群？

Question

我正在尝试通过 ansible 在 docker 中运行 etcd 集群。

我使用 docker_container ansible 模块，这就是我所拥有的：

- name: Run etcd KV node
      docker_container:
        name: "etcd0"
        image: quay.io/coreos/etcd
        network_mode: host
        command: [ "/usr/local/bin/etcd", \
        "-name etcd0", \
        "-advertise-client-urls http://{{ ansible_default_ipv4['address'] }}:2379,http://{{ ansible_default_ipv4['address'] }}:4001", \
        "-listen-client-urls http://0.0.0.0:2379,http://0.0.0.0:4001", \
        "-initial-advertise-peer-urls http://{{ ansible_default_ipv4['address'] }}:2380", \
        "-initial-cluster etcd0=http://{{ ansible_default_ipv4['address'] }}:2380", \
        "-initial-cluster-token etcd-cluster", \
        "-listen-peer-urls http://0.0.0.0:2380", \
        "-initial-cluster-state new" ]

这在单模式下工作，但是超过 1 个节点会出现问题，因为 etcd 参数 -initial-cluster 应该包含所有节点，例如，在 3 个节点的情况下：

-initial-cluster etcd0=http://192.168.12.50:2380,etcd1=http://192.168.12.51:2380,etcd2=http://192.168.12.52:2380

我不知道如何遍历所有节点并构建此字符串以运行一个 docker 容器。有可能吗？

Answer 1

hostvars 魔法变量为您服务：

- name: Generate useful facts for current node 1
  set_fact:
    ip_addr: "{{ ansible_default_ipv4.address }}"
    etcd_name: "etcd{{ ansible_play_hosts.index(inventory_hostname) }}"

- name: Generate useful facts for current node 2
  set_fact:
    etcd_uri: "{{ etcd_name }}=http://{{ ip_addr }}:2380"

- name: Run etcd KV node
  docker_container:
    name: "{{ etcd_name }}"
    image: quay.io/coreos/etcd
    network_mode: host
    command:
      - /usr/local/bin/etcd
      - -name {{ etcd_name }}
      - -advertise-client-urls http://{{ ip_addr }}:2379,http://{{ ip_addr }}:4001
      - -listen-client-urls http://0.0.0.0:2379,http://0.0.0.0:4001
      - -initial-advertise-peer-urls http://{{ ip_addr }}:2380
      - -initial-cluster {{ ansible_play_hosts | map('extract',hostvars,'etcd_uri') | list | join(',') }}
      - -initial-cluster-token etcd-cluster
      - -listen-peer-urls http://0.0.0.0:2380
      - -initial-cluster-state new

附：我还稍微重新格式化了您的 command 参数。