MySQL

MySQL+Keepalived实现双机热备

文章目录
  1. 1. 前言
  2. 2. 环境
  3. 3. keepalived的安装
  4. 4. keepalived相关文件复制到系统对应的目录下
  5. 5. keepalived 配置
  6. 6. 测试

前言

MySQL的安装与节点间的同步复制在这就不在阐述，大家可以查看文档MySQL5.6在CentOS6.6安装步骤和MySQL5.6.25节点复制

环境

MySQL-VIP：192.168.11.200
MySQL-Master：192.168.11.128
MySQL-Slave：192.168.11.129

OS版本：CentOS 6.6
MySQL版本：5.6.25
Keepalived版本：1.2.19

keepalived的安装

首先在安装keepalived之前检查下是否安装了openssl
shell> rpm -qa|grep openssl
查的结果表示已经安装了或者需要安装

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shell>yum –y install openssl-devel

下载解压安装keepalived

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shell>wget http://www.keepalived.org/software/keepalived-1.2.19.tar.gz
shell>tar -zxvf keepalived-1.2.19.tar.gz
shell>cd keepalived-1.2.19
shell>./configure --prefix=/usr/local/keepalived
shell>make
shell>make install

keepalived相关文件复制到系统对应的目录下

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shell>cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/rc.d/init.d
shell>cp /usr/local/keepalived/etc/sysconfig/keepalived  /etc/sysconfig/
shell>mkdir /etc/keepalived
shell>cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
shell>cp /usr/local/keepalived/sbin/keepalived  /usr/sbin/

keepalived 配置

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shell>vi /etc/keepalived/keepalived.cnf
! Configuration File for keepalived
global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.11.128
   smtp_connect_timeout 30
   router_id LVS_DEVEL
}

vrrp_instance VI_1 {
    state MASTER 	#MASTER|SLAVE
    interface eth0	#虚拟IP绑定网卡
    virtual_router_id 51 #节点中必须相同
    priority 100		#优先级
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        192.168.11.200 #虚拟IP
        192.168.11.201
    }
}

virtual_server 192.168.11.200 3306 {
    delay_loop 2	#每个6秒检查一次real_server状态
    lb_algo rr
    lb_kind DR
    nat_mask 255.255.255.0
    persistence_timeout 50 #会话保持时间
    protocol TCP
	
    real_server 192.168.11.128 3306 {
       weight 1
		notify_down /usr/local/mysql/bin/mysql.sh	#检查到服务down后执行脚本
        TCP_CHECK { 
			connect_timeout 10 #连接超时时间
			nb_get_retry 3 #重连次数
			delay_before_retry 3 #重连间隔时间
			connect_port 3306 #健康检查端口
        } 
    }
}

编写检测服务down后所执行的脚本

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shell>vi /usr/local/mysql/bin/mysql.sh
#杀掉keepalived 的进程
pkill keepalived
shell> chmod 744 /usr/local/mysql/bin/mysql.sh

注：此脚本是上面配置文件notify_down选项所用到的，keepalived使用notify_down选项来检查real_server的服务状态，当发现real_server服务故障时，便触发此脚本；我们可以看到，脚本就一个命令，通过pkill keepalived强制杀死keepalived进程，从而实现了MySQL故障自动转移。另外，我们不用担心两个MySQL会同时提供数据更新操作，因为每台MySQL上的keepalived的配置里面只有本机MySQL的IP+VIP，而不是两台MySQL的IP+VIP
在这样只有一个vrrp_instance 的环境里，主负载均衡器(MASTER)与备份负载均衡器（BACKUP）配置文件的差异一共只有3处: 全局定义的route_id、vrrp_instance state已经vrrp_instance的优先级priority

测试

启动MySQL ,keepalived

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sheel>service mysqld start
sheel>service keepalived start
sheel>service iptables stop

查看vip 是否已经帮到到了网卡eth0

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shell>ip a


关闭myql服务或vip已经绑定在了192.18.11.129上了表示测试成功