1、環境描述：

    OS：CentOS6.5_X64
    MASTER：192.168.0.202
    BACKUP：192.168.0.203
    VIP：192.168.0.204

2、配置兩臺Mysql主主同步

關於MySQL的安裝大家也可以參考《 MySQL之——CentOS6.5 編譯安裝MySQL5.6.16 》，主主同步在主從同步的基礎上將從伺服器配置為之前主伺服器的Master，相當於在原來主從同步的基礎上，將原來的Slave設定為了原來Master的Master，大家也可以參考《MySQL之——MS主從複製(讀寫分離)實現》 ，設定A為B的Master，B為A的Slave後，然後再將B設定為A的Master,A設定為B的Slave。

[[email protected] ~]# yum install mysql-server mysql -y
[[email protected] ~]# service mysqld start
[[email protected] ~]# mysqladmin -u root proot
[[email protected] ~]# vi /etc/my.cnf  #開啟二進位制日誌，設定id
[mysqld]
server-id = 1                    #backup這臺設定2
log-bin = mysql-bin
binlog-ignore-db = mysql,information_schema       #忽略寫入binlog日誌的庫
auto-increment-increment = 2             #欄位變化增量值
auto-increment-offset = 1              #初始欄位ID為1
slave-skip-errors = all                       #忽略所有複製產生的錯誤     
[
 
[email protected] ~]# service mysqld restart

#先檢視下log bin日誌和pos值位置

master配置如下：

[[email protected] master ~]# mysql -u root -proot
mysql> GRANT  REPLICATION SLAVE ON *.* TO 'replication'@'192.168.0.%' IDENTIFIED  BY 'replication';
mysql> flush  privileges;
mysql> change  master to
    ->  master_host='192.168.0.203',
    ->  master_user='replication',
    ->  master_password='replication',
    ->  master_log_file='mysql-bin.000002',
    ->  master_log_pos=106;  #對端狀態顯示的值
mysql> start  slave;         #啟動同步
 

backup配置如下：

[[email protected] ~]#  mysql -u root -proot
mysql> GRANT  REPLICATION SLAVE ON *.* TO 'replication'@'192.168.0.%' IDENTIFIED  BY 'replication';
mysql> flush  privileges;
mysql> change  master to
    ->  master_host='192.168.0.202',
    ->  master_user='replication',
    ->  master_password='replication',
    ->  master_log_file='mysql-bin.000002',
    ->  master_log_pos=106;
mysql> start  slave;

#主主同步配置完畢，檢視同步狀態Slave_IO和Slave_SQL是YES說明主主同步成功。

在master插入資料測試下：

在backup檢視是否同步成功：

可以看到已經成功同步過去，同樣在backup插入到user表資料，一樣同步過去，雙主就做成功了。

3、配置keepalived實現熱備

[[email protected] ~]# yum install -y pcre-devel openssl-devel popt-devel #安裝依賴包 

[[email protected] ~]# wget http://www.keepalived.org/software/keepalived-1.2.7.tar.gz
[[email protected] ~]# tar zxvf keepalived-1.2.7.tar.gz
[[email protected] ~]# cd keepalived-1.2.7
[[email protected] ~]#./configure --prefix=/usr/local/keepalived
make

#將keepalived配置成系統服務

[[email protected] ~]# cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
[[email protected] ~]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
[[email protected] ~]# mkdir /etc/keepalived/
[[email protected] ~]# cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/
[[email protected] ~]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/

[[email protected] ~]# vi /etc/keepalived/keepalived.conf
! Configuration File forkeepalived
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      #標識，雙主相同
 }
vrrp_instance VI_1 {
 state BACKUP           #兩臺都設定BACKUP
 interface eth0
 virtual_router_id 51       #主備相同
 priority 100           #優先順序，backup設定90
 advert_int 1
 nopreempt             #不主動搶佔資源，只在master這臺優先順序高的設定，backup不設定
 authentication {
 auth_type PASS
 auth_pass 1111
 }
 virtual_ipaddress {
 192.168.0.204
 }
}
virtual_server 192.168.0.204 3306 {
 delay_loop 2
 #lb_algo rr              #LVS演算法，用不到，我們就關閉了
 #lb_kind DR              #LVS模式，如果不關閉，備用伺服器不能通過VIP連線主MySQL
 persistence_timeout 50  #同一IP的連線60秒內被分配到同一臺真實伺服器
 protocol TCP
 real_server 192.168.0.202 3306 {   #檢測本地mysql，backup也要寫檢測本地mysql
 weight 3
 notify_down /usr/local/keepalived/mysql.sh    #當mysq服down時，執行此指令碼，殺死keepalived實現切換
 TCP_CHECK {
 connect_timeout 3    #連線超時
 nb_get_retry 3       #重試次數
 delay_before_retry 3 #重試間隔時間
  }
}

[[email protected] ~]# vi /usr/local/keepalived/mysql.sh
#!/bin/bash
pkill keepalived
[[email protected] ~]# chmod +x /usr/local/keepalived/mysql.sh
[[email protected] ~]# /etc/init.d/keepalived start

#backup伺服器只修改priority為90、nopreempt不設定、real_server設定本地IP。

#授權兩臺Mysql伺服器允許root遠端登入，用於在其他伺服器登陸測試！

mysql> grant all on *.* to'root'@'192.168.0.%' identified by 'root';
mysql> flush privileges;

4、測試高可用性

1)通過Mysql客戶端通過VIP連線，看是否連線成功。
2)停止master這臺mysql服務，是否能正常切換過去，可通過ip addr命令來檢視VIP在哪臺伺服器上。
3)可通過檢視/var/log/messges日誌，看出主備切換過程
4)master伺服器故障恢復後，是否主動搶佔資源，成為活動伺服器。
注意：服務啟動的順序：先啟動MySQL,後啟動Keepalived。