Ansible 使用 dnf 安裝 Redis Cluster (Redis6)

之前筆記 Ansible 安裝 Redis Cluster 紀錄到在 CentOS 7 上透過 Ansible 使用 yum 來安裝 Redis Cluster，但最近 production 環境已經升級成 CentOS 8 + dnf，所以來更新一下 Ansible script，避免之後想抄又要東翻西找XD

基本環境說明

  1. Azure VM B2s (2 vcpu,4GiB memory)
  2. OpenLogic CentOS 8.2
  3. Redis 6.0.8
  4. ansible 2.10.2

Ansible 腳本

  1. 專案結構

    • roles
      • redis-cluster
        • defaults
          • main.yml
        • handlers
          • main.yml
        • tasks
          • checkdir.yml
          • createcluster.yml
          • installredis.yml
          • installtools.yml
          • main.yml
          • prepareservice.yml
          • prepareredisconfig.yml
          • uninstall.yml
          • upgrade.yml
        • templates
          • config.j2
          • service.j2
        • vars
          • main.yml
        • inventories
          • dev.ini
        • README.md
    • ansible.cfg
    • main.yml

  2. 完整內容

    • roles

      • redis-cluster

        • defaults

          • main.yml

            ---
purpose: update

        • handlers

          • main.yml

            ---
- name: "Restart Redis Service"
listen: restart-service
systemd:
  name: "redis_{{item}}"
  daemon_reload: yes
  enabled: yes
  state: restarted
with_items: "{{redis_ports}}"

        • tasks

          • checkdir.yml

            ---
- name: Ensures dir exists
file:
  path: "{{ folder }}"
  state: directory
  mode: 0755
  owner: redis
  group: redis
  recurse: yes

          • createcluster.yml

            ---
- name: Create Cluster debug
debug:
  msg: redis-cli -a {{redispass}} --cluster-replicas 1 --cluster create {% for redis_node in groups['redis_all'] %} {% for redis_port in hostvars[redis_node].redis_ports %} {{ hostvars[redis_node].ip }}:{{ redis_port }} {% endfor %}{% endfor %}

- name: Create Cluster
shell: |
  echo "yes" |redis-cli -a {{redispass}} --cluster-replicas 1 --cluster create {% for redis_node in groups['redis_all'] %} {% for redis_port in hostvars[redis_node].redis_ports %} {{ hostvars[redis_node].ip }}:{{ redis_port }} {% endfor %}{% endfor %}

          • installredis.yml

            ---
- name: Install Redis
dnf:
  name: "{{redisversion}}"
  enablerepo:  remi
  state: latest

          • installtools.yml

            - name: Install rpm
dnf:
  name: 'https://rpms.remirepo.net/enterprise/remi-release-8.rpm'
  state: present
  disable_gpg_check: yes

- name: Enable remi repo
shell: dnf module enable -y redis:remi-6.0

- name: Insall Redis
include_tasks: installredis.yml

- name: check dir
include_tasks: checkdir.yml
vars:
  folder: "/etc/redis"

- name: Remove default redis service
ignore_errors: yes
shell: |
  systemctl disable redis 

- name: Delete redis service
ignore_errors: yes
file:
  path: "{{ item }}"
  state: absent
with_items:
  - /usr/lib/systemd/system/redis.service
  - /etc/systemd/system/redis.service.d
  - /etc/systemd/system/redis-sentinel.service.d

- name: Disable SELinux
shell: |
  setenforce 0
  sed -i 's/SELINUX=enforcing/SELINUX=disabled/g' /etc/selinux/config

- name: Allow Overcommit Memory
sysctl:
  name: vm.overcommit_memory
  value: "1"
  state: present
  reload: yes
  ignoreerrors: yes

- name: Stop and disable firewalld.
service:
  name: firewalld
  state: stopped
  enabled: False

          • main.yml

            ---
- name: Uninstall
include_tasks: uninstall.yml
when: purpose == 'uninstall' or purpose == 'reinstall'

- name: Install rpm and redis
include_tasks: installtools.yml
when: purpose == 'install'

- name: Upgrde redis
include_tasks: upgrade.yml
when: purpose == 'upgrade'

- name: create linux user
shell: |
  groupadd --system redis
  useradd -s /sbin/nologin --system -g redis redis
ignore_errors: yes
when: purpose == 'install'

- name: Generate redis config file
include_tasks: prepareredisconfig.yml
when: purpose != 'uninstall'

- name: Generate service file
include_tasks: prepareservice.yml
when: purpose == 'install' or purpose == 'reinstall'

- name: Restart Service
debug:
  msg: restart service
notify: restart-service
changed_when: true
when: purpose != 'uninstall'

- meta: flush_handlers

- name: Run cluster creation script
include_tasks: createcluster.yml
run_once: true
when: purpose == 'install' or purpose == 'reinstall'

          • prepareredisconfig.yml

            ---
- name: check dir - /etc/redis/redis_{{ item }}
include_tasks: checkdir.yml
vars:
  folder: "/etc/redis/redis_{{ item }}"
with_items: "{{ redis_ports }}"

- name: Prepare Configs
vars:
  redis_port: "{{item}}"
template:
  src: config.j2
  dest: "/etc/redis/redis_{{ item }}.conf"
  owner: redis
notify: restart-service
with_items:  "{{redis_ports}}"

          • prepareservice.yml

            ---
- name: Prepare services
vars:
  redis_port: "{{item}}"
template:
  src: service.j2
  dest: "/etc/systemd/system/redis_{{item}}.service"
  owner: redis
  group: redis
with_items: "{{redis_ports}}"

          • uninstall.yml

            - name: Stop Service
  service:
    name: "redis_{{item}}"
    state: stopped
  with_items: "{{ redis_ports }}"

- name: Disable Service
  shell: systemctl disable redis_{{item}}
  with_items: "{{ redis_ports }}"

- name: Delete config
  file:
    path: "/etc/redis/redis_{{item}}.conf"
    state: absent
  with_items: "{{ redis_ports }}"

- name: Delete service
  file:
    path: "/etc/systemd/system/redis_{{item}}.service"
    state: absent
  with_items: "{{ redis_ports }}"

- name: Recursively remove directory
  file:
    path: /etc/redis/redis_{{item}}
    state: absent
  with_items: "{{ redis_ports }}"

- name: Remove directory
  file:
    path: /etc/redis/
    state: absent

          • upgrade.yml

            ---
- include_tasks: installredis.yml

        • templates

          • config.j2

            dir /etc/redis/redis_{{redis_port}}
bind {{ip}} 127.0.0.1
requirepass {{redispass}}
masterauth {{redispass}}
port {{redis_port}}
pidfile /var/run/redis_{{redis_port}}.pid
maxclients 100000
# 啟用 redis cluster
cluster-enabled yes
# 每個 node 需要獨立，cluster 自行維護使用，不需人為介入
cluster-config-file nodes_{{redis_port}}.conf
# node 判斷失效的時間
cluster-node-timeout 5000
maxmemory-policy volatile-lru
loglevel notice

          • service.j2

            [Unit]
Description=Redis persistent key-value database
After=network.target
After=network-online.target
Wants=network-online.target

[Service]
ExecStart=/usr/bin/redis-server /etc/redis/redis_{{redis_port}}.conf --supervised systemd

ExecStop=/usr/libexec/redis-shutdown redis/redis_{{redis_port}}
Type=notify
User=redis
Group=redis
RuntimeDirectory=redis_{{redis_port}}
RuntimeDirectoryMode=0755
LimitNOFILE=10000000
LimitCORE=infinity
LimitNPROC=infinity
LimitMEMLOCK=infinity

[Install]
WantedBy=multi-user.target

        • vars

          • main.yml

            redispass: pass.123
redisversion: redis-0:6.0.8-1.el8.remi.x86_64

        • inventories

          • dev.ini

          ansible_host 是外網 ip 而 ip 則為內網 ip，如果 ansible client 是在內網，可以精簡為 ansible_host 就好

            [redis_all]
  redis1 ansible_host=10.0.1.5 ip=10.0.1.5 ansible_ssh_user=root ansible_ssh_pass=pass.123 redis_ports=7000,7003
  redis2 ansible_host=10.0.1.6 ip=10.0.1.6  ansible_ssh_user=root ansible_ssh_pass=pass.123 redis_ports=7001,7004
  redis3 ansible_host=10.0.1.7 ip=10.0.1.7 ansible_ssh_user=root ansible_ssh_pass=pass.123 redis_ports=7002,7005

        • README.md

          ## 全新安裝

          bash ansible-playbook -i roles/redis-replication/inventories/dev.ini -e “purpose=install” main.yml

          
## 重新安裝

  > 先 uninstall 並排除安裝基本套件

          bash ansible-playbook -i roles/redis-replication/inventories/dev.ini -e “purpose=reinstall” main.yml

          
## 更新 config

          bash ansible-playbook -i roles/redis-replication/inventories/dev.ini main.yml

          
## 升級

          ansible-playbook -i roles/redis-replication/inventories/dev.ini -e “purpose=upgrade” main.yml

          ## restart service

          ansible-playbook -i roles/redis-replication/inventories/dev.ini -e “purpose=restart” main.yml

    • ansible.cfg

      [defaults]
host_key_checking = False
roles_path = ./roles

    • main.yml

      - hosts: redis_all
roles:
  - redis-cluster

心得

大致上流程與之前筆記 Ansible 安裝 Redis Cluster 相同，主要變動的部份是

  1. dnf module 的註冊與啟用
  2. 使用 dnf 的 module 進行安裝

完整程式可以參考 yowko/ansible-dnf-install-redis-cluster

參考資訊

  1. Ansible 安裝 Redis Cluster
  2. yowko/ansible-dnf-install-redis-cluster