MySQL - Detailed explanation of dual-machine HA based on Keepalived (picture and text)

[root@masterr ~]# yum install mysql-server mysql -y
[root@masterr ~]# service mysqld start
[root@masterr ~]# mysqladmin -u root proot
[root@masterr ~]# vi /etc/my.cnf  #开启二进制日志，设置id
[mysqld]
server-id = 1                    #backup这台设置2
log-bin = mysql-bin
binlog-ignore-db = mysql,information_schema       #忽略写入binlog日志的库
auto-increment-increment = 2             #字段变化增量值
auto-increment-offset = 1              #初始字段ID为1
slave-skip-errors = all                       #忽略所有复制产生的错误     
[root@masterr ~]# service mysqld restart

[root@ master ~]# mysql -u root -proot
mysql> GRANT  REPLICATION SLAVE ON *.* TO 'replication'@'192.168.0.%' IDENTIFIED  BY 'replication';
mysql> flush  privileges;
mysql> change  master to
    ->  master_host='192.168.0.203',
    ->  master_user='replication',
    ->  master_password='replication',
    ->  master_log_file='mysql-bin.000002',
    ->  master_log_pos=106;  #对端状态显示的值
mysql> start  slave;         #启动同步

[root@backup ~]#  mysql -u root -proot
mysql> GRANT  REPLICATION SLAVE ON *.* TO 'replication'@'192.168.0.%' IDENTIFIED  BY 'replication';
mysql> flush  privileges;
mysql> change  master to
    ->  master_host='192.168.0.202',
    ->  master_user='replication',
    ->  master_password='replication',
    ->  master_log_file='mysql-bin.000002',
    ->  master_log_pos=106;
mysql> start  slave;

[root@masterr ~]# cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
[root@masterr ~]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
[root@masterr ~]# mkdir /etc/keepalived/
[root@masterr ~]# cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
[root@masterr ~]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/

[root@masterr ~]# vi /etc/keepalived/keepalived.conf
! Configuration File forkeepalived
global_defs {
notification_email {
test@sina.com
 }
notification_email_from  admin@test.com
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id MYSQL_HA      #标识，双主相同
 }
vrrp_instance VI_1 {
 state BACKUP           #两台都设置BACKUP
 interface eth0
 virtual_router_id 51       #主备相同
 priority 100           #优先级，backup设置90
 advert_int 1
 nopreempt             #不主动抢占资源，只在master这台优先级高的设置，backup不设置
 authentication {
 auth_type PASS
 auth_pass 1111
 }
 virtual_ipaddress {
 192.168.0.204
 }
}
virtual_server 192.168.0.204 3306 {
 delay_loop 2
 #lb_algo rr              #LVS算法，用不到，我们就关闭了
 #lb_kind DR              #LVS模式，如果不关闭，备用服务器不能通过VIP连接主MySQL
 persistence_timeout 50  #同一IP的连接60秒内被分配到同一台真实服务器
 protocol TCP
 real_server 192.168.0.202 3306 {   #检测本地mysql，backup也要写检测本地mysql
 weight 3
 notify_down /usr/local/keepalived/mysql.sh    #当mysq服down时，执行此脚本，杀死keepalived实现切换
 TCP_CHECK {
 connect_timeout 3    #连接超时
 nb_get_retry 3       #重试次数
 delay_before_retry 3 #重试间隔时间
  }
}

[root@masterr ~]# vi /usr/local/keepalived/mysql.sh
#!/bin/bash
pkill keepalived
[root@masterr ~]# chmod +x /usr/local/keepalived/mysql.sh
[root@masterr ~]# /etc/init.d/keepalived start

mysql> grant all on *.* to'root'@'192.168.0.%' identified by 'root';
mysql> flush privileges;