keepalived+mysql

 【操作系统版本】CentOS 5.4（64位）

【Keepalived版本】1.1.19

1.2．0以上在此系统上有问题，所以选择较低版本。

使用keepadlived ，在数据库主机和备用机上同时开启该程序，通过虚拟VIP地址对外提供数据库访问接口。并抢占VIP地址，正常情况下数据库主机VIP地址具有优先权，并提供数据库访问服务。在数据库主机数据库无法访问时，keep自动关闭程序注销VIP地址，同时备用机抢占VIP地址，数据库备用机将自动接管并顶替主机数据库。

【编译】

#./configure --prefix=/usr/local/keepalived --with-kernel-dir=/usr/src/kernels/2.6.18-164.el5-x86_64/

【安装】

#make && make install

#cp /usr/local/keepalived/etc/sysconfig/keepalived  /etc/sysconfig

#cp /usr/local/keepalived/etc/rc.d/init.d/keepalived  /etc/rc.d/keepalived

#vi /usr/local/MySQL/bin/MySQL.sh
 #!/bin/sh
 service keepalived stop

#chmod +x /usr/local/MySQL/bin/MySQL.sh

#mkdir /etc/keepalived/

#vi /etc/keepalived.conf

##AB机均按以上步骤安装。

【主机A配置】

! Configuration File for keepalived

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

     }

vrrp_instance VI_1 {

     state MASTER   #两台配置此处均是BACKUP

     interface eth0

     virtual_router_id 51

     priority 100   #优先级，另一台改为90

     advert_int 1

     nopreempt  #不抢占，只在优先级高的机器上设置即可，优先级低的机器不设置

     authentication {

     auth_type PASS

     auth_pass 1111

     }

     virtual_ipaddress {

     192.168.0.250

     }

     }

virtual_server 192.168.0.250 3306 {

     delay_loop 2   #每个2秒检查一次real_server状态

     lb_algo wrr   #LVS算法

     lb_kind DR    #LVS模式

     persistence_timeout 60   #会话保持时间

     protocol TCP

     real_server 192.168.0.245 3306 {

     weight 3

     notify_down "/usr/local/MySQL/bin/MySQL.sh"  #检测到服务down后执行的脚本

     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

     }

     }

【主机B 配置】

! Configuration File for keepalived

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

     }

vrrp_instance VI_1 {

     state BACKUP

     interface eth0

     virtual_router_id 51

     priority 90

     advert_int 1

     authentication {

     auth_type PASS

     auth_pass 1111

     }

     virtual_ipaddress {

     192.168.0.250

     }

     }

virtual_server 192.168.0.250 3306 {

     delay_loop 2

     lb_algo wrr

     lb_kind DR

     persistence_timeout 60

     protocol TCP

     real_server 192.168.0.246 3306 {

     weight 3

     notify_down /usr/local/MySQL/bin/MySQL.sh

     TCP_CHECK {

     connect_timeout 10

     nb_get_retry 3

     delay_before_retry 3

     connect_port 3306

     }

     }

【开启服务】

/usr/local/keepalived/sbin/keepalived -D