使用keepalived实现对mysql主从复制的主备自动切换.doc

keepalived实现对mysql主从复制的主备自动切换 使用MySQL+keepalived是一种非常好的解决方案，在MySQL-HA环境中，MySQL互为主从关系，这样就保证了两台 MySQL数据的一致性，然后用keepalived实现虚拟IP，通过keepalived自带的服务监控功能来实现MySQL故障时自动切换。 实验环境中用两台主机搭建了一个mysql主从复制的环境，两台机器分别安装了keepalived，用一个虚IP实现mysql服务器的主备自动切换功能.模拟环境：VIP：97 ：虚拟IP地址Master：98 ：主数据库IP地址Slave：99 ：从数据库IP地址备注：MySQL的主从同步配置不在此文档中说明（前提：主从同步已完成）安装步骤：1、keepalived的安装 Yum install -y keepalived Chkconfig keepalived on 2、keepalived.conf文件的配置Master：keepalived.confvi /etc/keepalived/keepalived.conf! Configuration File for keepalived global_defs notification_email notification_email_from smtp_connect_timeout 3 smtp_server router_id MySQL-ha vrrp_script check_run #声明vrrp_script 的函数check_run script /root/keepalived_check_mysql.sh #监控MySQL的脚本 interval 5 vrrp_sync_group VG1 group VI_1 vrrp_instance VI_1 state MASTER #指定主服务器节点为主节点，备用节点上设置需一致 interface eth0 #指定虚拟IP的网络接口 virtual_router_id 88 #VRRP组名，两个节点的设置必须一样，以指明各个节点属于同一VRRP组 priority 100 #主节点的优先级（1-254之间），备用节点必须比主节点优先级低。 advert_int 1 #组播信息发送间隔，两个节点设置必须一样 nopreempt authentication #设置验证信息，两个节点必须一致 auth_type PASS auth_pass 1111 track_script #调用函数代码块 check_run virtual_ipaddress #虚拟IP（对外提供MySQL服务的IP地址） 97 #不能和网内其他IP地址冲突 Slave：keepalived.conf! Configuration File for keepalived global_defs notification_email notification_email_from smtp_connect_timeout 3 smtp_server router_id MySQL-ha vrrp_script check_run script /root/keepalived_check_mysql.sh interval 5 vrrp_sync_group VG1 group VI_1 vrrp_instance VI_1 state MASTER interface eth1 #本地网口 按实际情况配置 virtual_router_id 88 priority 99 advert_int 1 nopreempt authentication auth_type PASS auth_pass 1111 track_script check_run virtual_ipaddress 97 3、 mysql状态检测脚本在目录root下创建脚本keepalived_check_mysql.sh：vim /root/keepalived_check_mysql.sh#!/bin/bashMYSQL=/usr/local/mysql/bin/mysqlMYSQL_HOST=localhostMYSQL_USER=rootMYSQL_PASSWORD=123456CHECK_TIME=3 #mysql is working MYSQL_OK is 1 , mysql down MYSQL_OK is 0 MYSQL_OK=1 function check_mysql_helth () $MYSQL -h $MYSQL_HOST -u $MYSQL_USER -p$MYSQL_PASSWORD -e show status; /dev/null 2&1 if $? = 0 ;then MYSQL_OK=1 else MYSQL_OK=0 fi return $MYSQL_OKwhile $CHECK_TIME -ne 0 do let CHECK_TIME -= 1 check_mysql_helthif $MYSQL_OK = 1 ; then CHECK_TIME=0 exit 0fiif $MYSQL_OK -eq 0 & $CHECK_TIME -eq 0 then pkill keepalived exit 1fisleep 1DoneChmod 755 /root/keepalived_check_mysql.sh4、 两台服务器同时启动mysql和keepalivedService keepalived restartService mysqld restart5、 功能验证 #Ip a :通过查看虚拟IP，验证keepalived服务是否启动 #tcpdump vrrp :查看vrrp通读记录，进行测试 由keepalived的配置文件可知，mysql关闭的话，将会执行keepalived_check_mysql.sh