MySQL高可用性之Keepalived+MySQL（双主热备）

Posted 2020-08-15 bcombettter

环境描述：
OS：CentOS6.5_X64
MASTER：192.168.0.202
BACKUP：192.168.0.203
VIP：192.168.0.204

1、配置两台mysql主主同步
[[email protected] ~]# yum install mysql-server mysql -y 
[[email protected] ~]# service mysqld start 
[[email protected] ~]# mysqladmin -u root password 123.com 
[[email protected] ~]# 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      
[[email protected] ~]# service mysqld restart

#先查看下log bin日志和pos值位置

master配置如下：

[[email protected] master ~]# mysql -u root -p123.com 
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

backup配置如下：

[[email protected] ~]#  mysql -u root -p123.com 
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;

#主主同步配置完毕，查看同步状态Slave_IO和Slave_SQL是YES说明主主同步成功。

在master插入数据测试下：

在backup查看是否同步成功：

可以看到已经成功同步过去，同样在backup插入到user表数据，一样同步过去，双主就做成功了。

2、配置keepalived实现热备
[[email protected] ~]# yum install -y pcre-devel openssl-devel popt-devel #安装依赖包

[[email protected] ~]# wget http://www.keepalived.org/software/keepalived-1.2.7.tar.gz 
[[email protected] ~]# tar zxvf keepalived-1.2.7.tar.gz 
[[email protected] ~]# cd keepalived-1.2.7 
[[email protected] ~]#./configure --prefix=/usr/local/keepalived 
make && make install

#将keepalived配置成系统服务

[[email protected] ~]# cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/ 
[[email protected] ~]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/ 
[[email protected] ~]# mkdir /etc/keepalived/ 
[[email protected] ~]# cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/ 
[[email protected] ~]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/

[[email protected] ~]# vi /etc/keepalived/keepalived.conf 
! Configuration File forkeepalived 
global_defs { 
notification_email { 
[email protected] 
 } 
notification_email_from  [email protected] 
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 
  } 
}

 

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

 

#backup服务器只修改priority为90、nopreempt不设置、real_server设置本地IP。

#授权两台Mysql服务器允许root远程登录，用于在其他服务器登陆测试！
mysql> grant all on *.* to‘root‘@‘192.168.0.%‘ identified by ‘123.com‘;
mysql> flush privileges;
3、测试高可用性
1、通过Mysql客户端通过VIP连接，看是否连接成功。
2、停止master这台mysql服务，是否能正常切换过去，可通过ip addr命令来查看VIP在哪台服务器上。

3、可通过查看/var/log/messges日志，看出主备切换过程
4、master服务器故障恢复后，是否主动抢占资源，成为活动服务器。