11 Mysql之配置双主热备+keeepalived.md

准备

 1. 双主 master1 192.168.199.49
         master2 192.168.199.50
     VIP 192.168.199.52  //虚拟IP
 2.环境 master:nginx + php + mysql + keepalived
        VIP:只要和master在一个局域网内即可。
 3. 服务器之间网络通畅，可以互相ping通。
 4. 2个服务器的mysql版本要一致。数据库密码一致
 5. 防火墙增加允许组播和允许VRRP（虚拟路由器冗余协）通信，这样主服务器在故障恢复后才能抢回资源
 -A INPUT -s 182.148.15.0/24 -d 224.0.0.18 -j ACCEPT
 -A INPUT -s 182.148.15.0/24 -p vrrp -j ACCEPT
 重启生效：service iptables reload

配置服务器

 服务器1：

 在my.cnf文件的[mysqld]配置区域添加下面内容：
 log-bin=mysql-bin   #记录二进制文件
 binlog_format=mixed #mysql默认采用的二进制格式
 server-id    = 2 #服务号，必须是唯一的，一般取IP的后8位
 expire_logs_days = 10   #binlog过期清理时间

 binlog-do-db = db1  #需要服务的数据库。
 #replicate-ignore-db = db3,mysql,test,information_schema,performance_schema,transfer_new #不需要复制的数据库
 #replicate-wild-ignore-table=garbage.% #有问题可以尝试使用此项配置
 sync_binlog = 1 #表示binlog日志在每1次写入后与硬盘同步，设置1最安全也最慢
 auto-increment-increment = 2 #服务器个数
 auto-increment-offset = 2 #自增偏移量，如果有2台，则一台设置1，另一台设置2
 slave-skip-errors = all #从库复制时跳过所有的错误
 服务器2：

 log-bin=mysql-bin
 binlog_format=mixed
 server-id = 1
 expire_logs_days = 10
 binlog-do-db = db1
 #replicate-ignore-db = db3,mysql,test,information_schema,performance_schema,transfer_new
 #replicate-wild-ignore-table=garbage.% #有问题可以尝试使用此项配置
 sync_binlog = 1
 auto-increment-increment = 2
 auto-increment-offset = 1
 slave-skip-errors = all

2台服务器都重启mysql服务：

 service mysql restart

同步配置(2台服务器分别执行)

 给对方授权复制权限

 //对方服务器60.205.182.26允许复制本服务器数据库，用户名repl 密码ocnt-123
 mysql> grant replication slave,replication client on *.* to repl@'60.205.182.26' identified by "ocnt-123";
 //生效
 mysql> flush privileges;
 //锁定表
 mysql> flush tables with read lock;

同步数据

 1.锁定表
 mysql> flush tables with read lock;
 2.同步数据，可使用navicat

同步操作(2台服务器分别执行)

 //查看各自服务器当前二进制日志文件名称和记录位置
 mysql> show master status;

 <!-----------------------服务器1同步------------------------------------>
 //解锁表
 mysql> unlock tables;
 //停止slave
 mysql> slave stop;
 //开始同步: IP、用户名和密码为服务器2刚才grant授权配置的,日志文件和pos值得位置通过服务器2 show master status查看得来
 mysql> change  master to  master_host='101.200.63.35',master_user='repl',master_password='',master_log_file='mysql-bin.000016',master_log_pos=363;
 //开启slave
 mysql> start slave;

 <!-----------------------服务器2同步------------------------------------>
 //解锁表
 mysql> unlock tables;
 //停止slave
 mysql> slave stop；
 <!--开始同步-->
 change  master to master_host='60.205.182.26',master_user='repl',master_password='',master_log_file='mysql-bin.000028',master_log_pos=107;
 <!--开启slave-->
 mysql> start slave;

查看同步状态，如下出现两个“Yes”，表明同步成功！（Slave_IO_Running和Slave_SQL_Running）

 mysql> show slave status \G;

配置到此处就完成了双主热备。

keepalived故障自动切换配置

 master1:192.168.199.49  主机1
 master2:192.168.199.50  主机2 备份
 VIP:192.168.199.52   虚拟IP
 ### 2台服务器安装keepalived

 [root@localhost ]#yum install -y openssl-devel
 [root@localhost src]#cd /usr/local/src/
 [root@localhost src]# wget http://www.keepalived.org/software/keepalived-1.3.5.tar.gz
 [root@localhost src]# tar -zvxf keepalived-1.3.5.tar.gz
 [root@localhost src]# cd keepalived-1.3.5
 [root@localhost keepalived-1.3.5]# ./configure --prefix=/usr/local/keepalived
 [root@localhost keepalived-1.3.5]# make && make install

 [root@localhost keepalived-1.3.5]# cp /usr/local/src/keepalived-1.3.5/keepalived/etc/init.d/keepalived /etc/rc.d/init.d/
 [root@localhost keepalived-1.3.5]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
 [root@localhost keepalived-1.3.5]# mkdir /etc/keepalived/
 [root@localhost keepalived-1.3.5]# cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
 [root@localhost keepalived-1.3.5]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/
 [root@localhost keepalived-1.3.5]# echo "/etc/init.d/keepalived start" >> /etc/rc.local

master1服务器配置

 [root@master1 ~]# cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
 [root@master1 ~]# vim /etc/keepalived/keepalived.conf       ＃删除所有内容，重新配置如下

 ! Configuration File for keepalived
 global_defs {
     notification_email {
         412140451@qq.com
     }

     notification_email_from 412140451@qq.com
     smtp_server 127.0.0.1
     smtp_connect_timeout 30
     router_id MASTER-HA
 }

 vrrp_script chk_mysql_port {     #检测mysql服务是否在运行
     script "/opt/chk_mysql.sh"   #这里通过脚本监测
     interval 3                   #脚本执行间隔，每3s检测一次
     weight -5                    #脚本结果导致的优先级变更，检测失败（脚本返回非0）则优先级 -5
     fall 2                    #检测连续2次失败才算确定是真失败。会用weight减少优先级（1-255之间）
     rise 1                    #检测1次成功就算成功。但不修改优先级
 }

 vrrp_instance VI_1 {
     state MASTER
     interface eth0      #指定虚拟ip的网卡接口
     mcast_src_ip 192.168.199.49 #本机master的 IP地址
     virtual_router_id 100    #路由器标识，MASTER和BACKUP必须是一致的
     priority 100 #定义优先级，数字越大，优先级越高，在同一个vrrp_instance下，MASTER的优先级必须大于BACKUP的优先级。这样MASTER故障恢复后，就可以将VIP资源再次抢回来
     advert_int 1
     authentication {   #加密协议
         auth_type PASS
         auth_pass 1111
     }
     virtual_ipaddress {
         192.168.199.52      #虚拟IP地址 VIP
     }

     track_script {
        chk_mysql_port
     }
 }

master2服务器配置 修改 mcast_src_ip priority

 global_defs {
     notification_email {
         412140451@qq.com
     }

     notification_email_from 412140451@qq.com
     smtp_server 127.0.0.1
     smtp_connect_timeout 30
     router_id MASTER-HA
 }

 vrrp_script chk_mysql_port {
     script "/opt/chk_mysql.sh"
     interval 3
     weight -5
     fall 2
     rise 1
 }

 vrrp_instance VI_1 {
     state BACKUP
     interface eth0
     mcast_src_ip 192.168.199.50
     virtual_router_id 100
     priority 90
     advert_int 1
     authentication {
         auth_type PASS
         auth_pass 1111
     }
     virtual_ipaddress {
         192.168.199.52
     }

     track_script {
        chk_mysql_port
     }
 }

2个服务器都编写检测切换mysql脚本

 KeepAlived做心跳检测，如果Master的MySQL服务挂了(3306端口挂了),那么它就会选择自杀。Slave的KeepAlived通过心跳检测发现这个情况，就会将VIP的请求接管
 vim /opt/chk_mysql.sh

 #!/bin/bash
 CHECK_TIME=3

 #Mysql
 host='localhost'
 port=''
 user='root'
 password='ocnt-123'
 mysqlclient="mysql"

 #mysql  is working MYSQL_OK is 1 , mysql down MYSQL_OK is 0
 function check_mysql_helth (){
     #NEW=$MYSQL -h $MYSQL_HOST -u $MYSQL_USER -p${MYSQL_PASSWORD} -e "show status;" >/dev/null 2>&1
     $mysqlclient --host=$host --port=$port --user=$user --password=$password  -e "show databases;" > /dev/null 2>&1

     if [ $? == 0 ]
         then
               MYSQL_OK=1
     else
               MYSQL_OK=0
     fi
 #    echo $MYSQL_OK
     return $MYSQL_OK
 }

 while [ $CHECK_TIME -ne 0 ]
 do
     let "CHECK_TIME -= 1"
     check_mysql_helth
 if [ $MYSQL_OK == 1 ] ; then
     CHECK_TIME=0
     exit 0
 fi
 if [ $MYSQL_OK -eq 0 ] &&  [ $CHECK_TIME -eq 0 ]
 then
     pkill keepalived
     exit 1
 fi
 sleep 1
 done

赋权限

 chmod 755 /opt/chk_mysql.sh

启动服务

 关闭防火墙
 service iptables stop
 启动服务
  /etc/init.d/keepalived start

数据库测试

 使用局域网内的客户端连接VIP
 mysql -h192.168.199.52 -uroot -pocnt-123
 测试是否可用

故障切换检测

 默认情况下，vip是在master1上的。使用"ip addr"命令查看vip切换情况
 ip addr
 查找
 inet 192.168.199.49/32 scope global eth0                              //这个32位子网掩码的vip地址表示该资源目前还在master1机器上，而master2机器上没有
 同时查看 tail -f /var/log/message 会发现
 Dec 13 17:52:38 localhost Keepalived_vrrp[65545]: VRRP_Instance(VI_1) Entering MASTER STATE
 Dec 13 17:52:38 localhost Keepalived_vrrp[65545]: VRRP_Instance(VI_1) setting protocol VIPs.
 Dec 13 17:52:38 localhost Keepalived_vrrp[65545]: Sending gratuitous ARP on eth0 for 192.168.199.51

 关掉master1的mysql服务
 service mysql stop
 查看 master1的日志 tail -f /var/log/message 会发现
 Dec 13 18:52:44 localhost Keepalived_vrrp[65545]: Stopped
 Dec 13 18:52:44 localhost Keepalived[65542]: Stopped Keepalived v1.3.5 (03/19,2017), git commit v1.3.5-6-g6fa32f2

 查看master2的日志
 Dec 13 18:52:45 localhost Keepalived_vrrp[28451]: VRRP_Instance(VI_1) Transition to MASTER STATE
 Dec 13 18:52:46 localhost Keepalived_vrrp[28451]: VRRP_Instance(VI_1) Entering MASTER STATE
 Dec 13 18:52:46 localhost Keepalived_vrrp[28451]: VRRP_Instance(VI_1) setting protocol VIPs.
 Dec 13 18:52:46 localhost Keepalived_vrrp[28451]: Sending gratuitous ARP on eth0 for 192.168.199.51

 此时就已经转移到master2上，
 恢复master1 的mysql服务
 service mysql start
 恢复master1 的keepalive
 /etc/init.d/keepalived start

 查看master1的日志
 Dec 13 18:54:41 localhost Keepalived_vrrp[71002]: VRRP_Instance(VI_1) Transition to MASTER STATE
 Dec 13 18:54:42 localhost Keepalived_vrrp[71002]: VRRP_Instance(VI_1) Entering MASTER STATE
 Dec 13 18:54:42 localhost Keepalived_vrrp[71002]: VRRP_Instance(VI_1) setting protocol VIPs.
 Dec 13 18:54:42 localhost Keepalived_vrrp[71002]: Sending gratuitous ARP on eth0 for 192.168.199.51

 查看master2的日志
 Dec 13 18:54:41 localhost Keepalived_vrrp[28451]: VRRP_Instance(VI_1) Received advert with higher priority 100, ours 90
 Dec 13 18:54:41 localhost Keepalived_vrrp[28451]: VRRP_Instance(VI_1) Entering BACKUP STATE
 Dec 13 18:54:41 localhost Keepalived_vrrp[28451]: VRRP_Instance(VI_1) removing protocol VIPs.

 说明服务已经转移到master2上了。
 至此完成

完成

其它：删除主从复制

 mysql> stop slave;
 mysql> slave reset;
 mysql> reset master;

keepalived

 启动
 /etc/init.d/keepalived start

异常解决办法

 如果不能正常复制，查看状态
 sql> show slave status \G;
 然后可以看到错误信息，一般情况下，重启一下slave就好了
 sql> stop slave;