3. 安裝MySQL-pxc

3.1. 說明

之前為了搭建高可用的MySQL的集群货矮，所以安裝MySQL-pxc稽揭，具體介紹可以看https://www.percona.com/software/mysql-database/percona-xtradb-cluster
不知道為什么服務(wù)器下載都巨慢登渣，所以我都使用離線安裝喷户。下載的是主要的包隙轻，還有其他一堆依賴需要服務(wù)器自己去下載始绍。

ansiblehosts文件

[mysqlservers]
sz-1 node_name=pxc1
sz-2 node_name=pxc2

3.2. yml腳本

---
- hosts: mysqlservers
  remote_user: root
  vars_files:
    - ../vars.yml

  tasks:
  - name: Ensure SELinux is set to enforcing mode
    lineinfile:
      path: /etc/selinux/config
      regexp: '^SELINUX='
      line: SELINUX=permissive
  - name: Copy rpm
    copy:
      src: "{{ PLAYBOOK_DIR }}/files/mysql"
      dest: /mnt
      owner: root
      group: root
      mode: 0755
  - name: install prepare
    yum:
      name: "/mnt/mysql/percona-release-latest.noarch.rpm"
      state: present

  - name: install pxc
    shell: "yum localinstall -y /mnt/mysql/Percona/*"

  - name: firewarld add 3306
    firewalld:
      port: 3306/tcp
      permanent: true
      immediate: true
      zone: public
      state: enabled
  - name: firewarld add 4444
    firewalld:
      port: 4444/tcp
      permanent: true
      immediate: true
      zone: public
      state: enabled
  - name: firewarld add 4567
    firewalld:
      port: 4567/tcp
      permanent: true
      immediate: true
      zone: public
      state: enabled
  - name: firewarld add 4568
    firewalld:
      port: 4568/tcp
      permanent: true
      immediate: true
      zone: public
      state: enabled
      
  - name: Copy config
    template:
      src: "{{ PLAYBOOK_DIR }}/mysql-pxc/templates/wsrep.cnf.j2"
      dest: /etc/percona-xtradb-cluster.conf.d/wsrep.cnf
      owner: root
      group: root
      mode: 0755

  - name: set SELinux to permissive
    shell: setenforce 0
    
  - name: start mysql@bootstrap
    service:
      name: mysql@bootstrap
      state: started
    when: inventory_hostname == groups['mysqlservers'][0]

因?yàn)槭谴罱和海枰葐?dòng)第一個(gè)節(jié)點(diǎn)，進(jìn)行配置完后再啟動(dòng)其他節(jié)點(diǎn)亏推，各節(jié)點(diǎn)會(huì)自動(dòng)建立鏈接学赛。

3.3. 模板文件

因?yàn)榇罱ǖ氖羌涵h(huán)境，因此都需要配置節(jié)點(diǎn)

3.3.1 wsrep.cnf.j2

[mysqld]
# Path to Galera library
wsrep_provider=/usr/lib64/galera3/libgalera_smm.so

# Cluster connection URL contains IPs of nodes
#If no IP is found, this implies that a new cluster needs to be created,
#in order to do that you need to bootstrap this node
wsrep_cluster_address=gcomm://{% set comma = joiner(",") %}
{% for item in groups['mysqlservers'] -%}
    {{ comma() }}{{ hostvars[item].inventory_hostname }}
{%- endfor %}

# In order for Galera to work correctly binlog format should be ROW
binlog_format=ROW

# MyISAM storage engine has only experimental support
default_storage_engine=InnoDB

# Slave thread to use
wsrep_slave_threads=8

wsrep_log_conflicts

# This changes how InnoDB autoincrement locks are managed and is a requirement for Galera
innodb_autoinc_lock_mode=2

# Node IP address
wsrep_node_address={{ ansible_default_ipv4.address }}
# Cluster name
wsrep_cluster_name=newtranx-pxc-cluster

#If wsrep_node_name is not specified,  then system hostname will be used
wsrep_node_name={{ node_name }}

#pxc_strict_mode allowed values: DISABLED,PERMISSIVE,ENFORCING,MASTER
pxc_strict_mode=ENFORCING

# SST method
wsrep_sst_method=xtrabackup-v2

#Authentication for SST method
wsrep_sst_auth=sstuser:passw0rd

3.4. 運(yùn)行ansible-playbook

ansible-playbook -i /etc/ansible/hosts mysql/main.yml

3.5. 基本配置

修改密碼吞杭、創(chuàng)建遠(yuǎn)程用戶盏浇、修改權(quán)限，這里不做贅述篇亭，參考之前寫的《Ansible部署系列：（六）安裝MySQL》

3.6. 啟動(dòng)其他節(jié)點(diǎn)

---
- hosts: mysqlservers
  remote_user: root
  vars_files:
    - ../vars.yml

  tasks:
    - name: set SELinux to permissive
      shell: setenforce 0
  
    - name: start mysql
      service:
        name: mysqld
        state: started
      when: inventory_hostname != groups['mysqlservers'][0]

3.7. 查看各節(jié)點(diǎn)狀態(tài)

show status like 'wsrep%';