之前的文章介绍了如何配置MysqL双主互备,见http://www.linuxidc.com/Linux/2013-05/83784.htm
这里介绍如何配合前者实现Keepalived双机热备
系统环境:CentOS6.3 x64
MysqL版本:MysqL-5.6.10
Keepalived版本:keepalived-1.2.7
MysqL-VIP:192.168.7.253
MysqL-master1:192.168.7.201
MysqL-master2:192.168.7.249
1.在MysqL-master1:192.168.7.201服务器上keepalived安装及配置
编译安装,实际以本机kernel版本为准
# wget http://www.keepalived.org/software/keepalived-1.2.7.tar.gz
# tar zxvf keepalived-1.2.7.tar.gz
# cd keepalived-1.2.7
# ./configure --prefix=/usr/local/keepalived --with-kernel-dir=/usr/src/kernels/2.6.32-
279.el6.x86_64
# make && make install
新建一个配置文件,默认keepalived启动会去/etc/keepalived目录下寻找配置文件
# mkdir /etc/keepalived
# vi /etc/keepalived/keepalived.conf
------------------
global_defs {
notification_email {
lzyangel@126.com
}
notification_email_from lzyangel@126.com
smtp_server stmp.126.com
smtp_connect_timeout 30
router_id MysqL-ha
}
vrrp_instance VI_1{
# 两台配置此处均是BACKUP
state BACKUP
# 注意网卡接口
interface eth0
virtual_router_id 51
# 优先级,另一台改为90
priority 100
advert_int 1
# 不主动抢占资源
nopreempt
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.7.253
}
}
virtual_server 192.168.7.253 3306 {
# 每个2秒检查一次real_server状态
delay_loop 2
# LVS算法
lb_algo wrr
# LVS模式
lb_kind DR
# 会话保持时间
persistence_timeout 60
protocol TCP
real_server 192.168.7.201 3306 {
weight 3
# 检测到服务down后执行的脚本
notify_down /etc/rc.d/keepalived.sh
TCP_CHECK {
# 连接超时时间
connect_timeout 10
# 重连次数
nb_get_retry 3
# 重连间隔时间
delay_before_retry 3
# 健康检查端口
connect_port 3306
}
}
----------------------
编写检测服务down后所要执行的脚本
# vi /etc/rc.d/keepalived.sh
-------------
#!/bin/sh
pkill keepalived
-------------
# chmod +x /etc/rc.d/keepalived.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.
启动keepalived
# /usr/local/keepalived/sbin/keepalived -D
查看连接状态
# ps -aux | grep keepalived
返回:
---------------
root 25348 0.0 0.0 36792 720 ? Ss 07:15 0:00
/usr/local/keepalived/sbin/keepalived -D
root 25349 0.5 0.1 40968 2016 ? S 07:15 0:00
/usr/local/keepalived/sbin/keepalived -D
root 25350 0.0 0.1 40968 1340 ? S 07:15 0:00
/usr/local/keepalived/sbin/keepalived -D
--------------------
测试
找一台局域网PC,然后去ping MysqL的VIP,这时候MysqL的VIP是可以ping的通的
停止MysqL服务,看keepalived健康检查程序是否会触发我们编写的脚本,去kill掉keepalived进程
# service MysqLd stop
# ps -aux | grep keepalived
无返回结果
2.在MysqL-master2:192.168.7.249服务器上keepalived安装及配置
编译安装,实际以本机kernel版本为准
# wget http://www.keepalived.org/software/keepalived-1.2.7.tar.gz
# tar zxvf keepalived-1.2.7.tar.gz
# cd keepalived-1.2.7
# ./configure --prefix=/usr/local/keepalived --with-kernel-dir=/usr/src/kernels/2.6.32-
279.el6.x86_64
# make && make install
新建一个配置文件,默认keepalived启动会去/etc/keepalived目录下寻找配置文件
# mkdir /etc/keepalived
# vi /etc/keepalived/keepalived.conf
------------------
global_defs {
notification_email {
lzyangel@126.com
}
notification_email_from lzyangel@126.com
smtp_server stmp.126.com
smtp_connect_timeout 30
router_id MysqL-ha
}
vrrp_instance VI_1{
# 两台配置此处均是BACKUP
state BACKUP
# 注意网卡接口
interface eth0
virtual_router_id 51
# 优先级,另一台改为90
priority 90
advert_int 1
# 不主动抢占资源
nopreempt
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.7.253
}
}
virtual_server 192.168.7.253 3306 {
# 每个2秒检查一次real_server状态
delay_loop 2
# LVS算法
lb_algo wrr
# LVS模式
lb_kind DR
# 会话保持时间
persistence_timeout 60
protocol TCP
real_server 192.168.7.249 3306 {
weight 3
# 检测到服务down后执行的脚本
notify_down /etc/rc.d/keepalived.sh
TCP_CHECK {
# 连接超时时间
connect_timeout 10
# 重连次数
nb_get_retry 3
# 重连间隔时间
delay_before_retry 3
# 健康检查端口
connect_port 3306
}
}
----------------------
编写检测服务down后所要执行的脚本
# vi /etc/rc.d/keepalived.sh
-------------
#!/bin/sh
pkill keepalived
-------------
# chmod +x /etc/rc.d/keepalived.sh
启动keepalived
# /usr/local/keepalived/sbin/keepalived -D
# ps -aux | grep keepalive
至此配置完成,网站后台只需要配置MysqL-VIP:192.168.7.253虚拟地址即可
这里实际连接的master数据库,以哪台master先开MysqL服务为准。
当master1:192.168.7.201 MysqL端口挡掉或者服务器异常关闭,keepalived会自动跳转到master2:192.168.7.249.
因为两台数据库的数据时同步的,用户访问的是MysqL-VIP:192.168.7.253虚拟地址,所以网站数据连接会无缝透明转接到master2服务器,实现双机热备+数据同步功能。保证网站数据库的实时可用性。
注:当某一台master服务器挂掉恢复后,需同时打开MysqL服务和keepalived服务,保证另一台服务器如果挂掉会无缝转接。
所以建议MysqL与keeplived设置服务开机启动。
# chkconfig MysqLd on
# vi /etc/rc.local
添加:
---------------
/usr/local/keepalived/sbin/keepalived -D