Linux下keepalived+mysql 实现高可用

Linux下keepalived+mysql实现高可用

首先在搭建前分析，想用keepalived实现mysql高可用，那么先的对keepalived+lvs跟mysql主主复制有所了解。因为mysql+keepalived架构是在keepalived+lvs跟mysql主主复制的基础上实现的lvs+keepalived跟mysql主主复制，在前面的博文中已经介绍过了这里不啰嗦了。

lvs+keepalived链接：http://duyunlong.blog.51cto.com/1054716/1118447,

mysql主主复制链接：http://duyunlong.blog.51cto.com/1054716/1306841

我们的目标是，两台mysql服务器如果其中有一台mysql服务器挂掉后，另外一台能立马接替其进行工作。因此我们就必须保证两台mysql数据库的数据完全一样，而且当挂掉的那一台重新启动的话，不再会被客户端继被访问，而是会充当备机跟现在工作的mysql进行数据同步，一直到提供服务的那台挂掉后再接替其工作。如此周而复始的实现了mysql的高可用。在通常情况下实现这种模式的keepalived无疑是最好的选择。因为有虚拟IP的原因，如果有一台mysql挂掉了，keepalived会从服务器群中剔除，而客户端访问会被切换到另外一台接替其工作的机器上。

在搭建的时候一些注意事项，mysql主主复制跟lvs+keepalived搭建的注意事情前面博文已经提高这里就不再啰嗦。在搭建完毕后，因为arp的原因不能够实现自由切换。这就是要注意的重点。

vim /etc/sysctl.conf
#.............前面部分省去
#######以下是文件末尾添加的部分######
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2
##这4行的主要作用是本地arp不作回应##

添加完后保存退出，并执行：sysctl -p使其生效

[root@mysql-ha1 ~] # sysctl -p
net.ipv4.ip_forward = 0
net.ipv4.conf.default.rp_filter = 1
net.ipv4.conf.default.accept_source_route = 0
kernel.sysrq = 0
kernel.core_uses_pid = 1
kernel.msgmnb = 65536
kernel.msgmax = 65536
kernel.shmmax = 68719476736
kernel.shmall = 4294967296
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0
net.ipv4.conf.eth0.send_redirects = 0
net.ipv4.conf.eth0.send_redirects = 0
net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2

下面具体操作，首先有两台mysql机器已经搭建好了mysql的主主复制

vip:192.168.5.55

mysql-ha1:192.168.5.234

mysql-ha2:192.168.5.155

在两台mysql机器上都安装ipvsadm,keepalived，首先在mysql-ha1(192.168.5.234)安装

[root@mysql-ha1 src] # wget http://www.keepalived.org/software/keepalived-1.2.2.tar.gz
[root@mysql-ha1 src] # wget http://www.linuxvirtualserver.org/software/kernel-2.6/ipvsadm-1.26.tar.gz
[root@mysql-ha1 src] # yum -y install kernel-devel make gcc openssl-devel libnl* popt*
[root@mysql-ha1 src] # ln -s /usr/src/kernels/2.6.32-220.13.1.el6.x86_64/ /usr/src/linux
[root@mysql-ha1 src] # tar -zxvf ipvsadm-1.26.tar.gz
[root@mysql-ha1 src] # cd ipvsadm-1.26/
[root@mysql-ha1 ipvsadm-1.26] # make
[root@mysql-ha1 ipvsadm-1.26] # make install
[root@mysql-ha1 ipvsadm-1.26] # cd ..
[root@mysql-ha1 src] # tar -zxvf keepalived-1.2.2.tar.gz
[root@mysql-ha1 src] # cd keepalived-1.2.2/
[root@mysql-ha1 keepalived-1.2.2] # ./configure --with-kernel-dir=/usr/src/kernels/2.6.32-358.2.1.el6.x86_64/
[root@mysql-ha1 keepalived-1.2.2] # make && make install
[root@mysql-ha1 keepalived-1.2.2] # cp /usr/local/etc/rc.d/init.d/keepalived /etc/rc.d/init.d/
[root@mysql-ha1 keepalived-1.2.2] # cp /usr/local/etc/sysconfig/keepalived /etc/sysconfig/
[root@mysql-ha1 keepalived-1.2.2] # mkdir /etc/keepalived
[root@mysql-ha1 keepalived-1.2.2] # cp /usr/local/etc/keepalived/keepalived.conf /etc/keepalived/
[root@mysql-ha1 keepalived-1.2.2] # cp /usr/local/sbin/keepalived /usr/sbin/

在mysql-ha2（192.168.5.155）也同样进行安装

然后我们编辑keepalived配置文件，下面是mysql-ha1（192.168.5.234）上的配置文件内容

[root@mysql-ha1 ~] # >/etc/keepalived/keepalived.conf
[root@mysql-ha1 ~] # vim /etc/keepalived/keepalived.conf
#! Configuration File for keepalived
global_defs {
router_id mysql-ha1  #修改为自己的主机名
             }
##################第一部分###################
vrrp_instance VI_1 {
     state BACKUP  #都修改成BACKUP
     interface eth0
     virtual_router_id 60  #默认51 主从都修改为60
     priority 100  #在mysql-ha2上LVS上修改成80
     advert_int 1
     nopreempt  #不抢占资源，意思就是它活了之后也不会再把主抢回来
     authentication {
     auth_type PASS
     auth_pass 1111
     }
virtual_ipaddress {
     192.168.5.55
     }
}
##################第二部分###################
virtual_server 192.168.5.55 3306 {
     delay_loop 6
     lb_algo wrr
     lb_kind DR
     nat_mask 255.255.255.0
     persistence_timeout 50
     protocol TCP
 real_server 192.168.5.234 3306 {
     weight 1
     notify_down /usr/local/mysql/bin/mysql.sh
     TCP_CHECK {
         connect_timeout 10
         nb_get_retry 3
         connect_port 3306
         }
     }
}

这里需要注意的是，notify_down /usr/local/mysql/bin/mysql.sh这个选项，这个是是在keepalived检测不到mysql的时候要执行的脚本，从上面的配置文件来看real服务器只有本机。那么，keeaplived如果启动，客户端也只是访问本机的mysql。nopreempt这个选下也得注意，这个是不抢占资源在优先级高的机器上配置就可以。

看下这个脚本的内容：

[root@mysql-ha1 ~] # vim /usr/local/mysql/bin/mysql.sh
#!/bin/bash
pkill keepalived
[root@mysql-ha1 ~] # chmod +x /usr/local/mysql/bin/mysql.sh

脚本内容就一条命令：pkill keepalived，主要作用是如果本机的mysql挂掉了，那么同时会杀死本机的keepalived，这样另外一台就会接替他工作，虚拟IP也会被另一台接管，如果不杀死keepalived虚拟IP不会被另一台接管，mysql访问也就不会切换过去。

测试下如果，mysql服务器挂掉，脚本是否可以杀死keepalived

[root@mysql-ha1 ~] # ps aux | grep keepalived
root      2518  0.0  0.0  41796   936 ?        Ss   19:35   0:00 keepalived -D
root      2519  0.0  0.1  43900  2152 ?        S    19:35   0:00 keepalived -D
root      2520  0.0  0.0  43900  1572 ?        S    19:35   0:00 keepalived -D
root      2610  0.0  0.0 103240   860 pts/0     S+   23:07   0:00  grep  keepalived
[root@mysql-ha1 ~] # netstat -ntlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program  name
tcp        0      0 0.0.0.0:3306                0.0.0.0:*                   LISTEN      2237/mysqld
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      1041/sshd
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      1416/master
tcp        0      0 0.0.0.0:5672                0.0.0.0:*                   LISTEN      1429/qpidd
tcp        0      0 :::22                       :::*                        LISTEN      1041/sshd
tcp        0      0 ::1:25                      :::*                        LISTEN      1416/master
[root@mysql-ha1 ~] # service mysqld stop
Shutting down MySQL... SUCCESS!
[root@mysql-ha1 ~] # ps aux | grep keepalived
root      2640  0.0  0.0 103240   856 pts/0     S+   23:07   0:00  grep  keepalived
[root@mysql-ha1 ~] # netstat -ntlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program  name
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      1041/sshd
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      1416/master
tcp        0      0 0.0.0.0:5672                0.0.0.0:*                   LISTEN      1429/qpidd
tcp        0      0 :::22                       :::*                        LISTEN      1041/sshd
tcp        0      0 ::1:25                      :::*                        LISTEN      1416/master
[root@mysql-ha1 ~] #

可以看到当mysqld服务器挂掉后，脚本生效同时杀死本机keepalived使得mysql故障转移。这时另一台keepalived会接替它工作。

同样看下mysql-ha2(192.168.5.155)上keepalived配置文件

[root@mysql-ha2 ~] # vim /etc/keepalived/keepalived.conf
#! Configuration File for keepalived
global_defs {
router_id mysql-ha1  #修改为自己的主机名
             }
##################第一部分###################
vrrp_instance VI_1 {
     state BACKUP  #都修改成BACKUP
     interface eth1
     virtual_router_id 60  #默认51 主从都修改为60
     priority 80  #在mysql-ha1上LVS上修改成100
     advert_int 1
     authentication {
     auth_type PASS
     auth_pass 1111
     }
virtual_ipaddress {
     192.168.5.55
     }
}
##################第二部分###################
virtual_server 192.168.5.55 3306 {
     delay_loop 6
     lb_algo wrr
     lb_kind DR
     nat_mask 255.255.255.0
     persistence_timeout 50
     protocol TCP
 real_server 192.168.5.155 3306 {
     weight 1
     notify_down /usr/local/mysql/bin/mysql.sh
     TCP_CHECK {
         connect_timeout 10
         nb_get_retry 3
         connect_port 3306
         }
     }
}

配置完毕后可以查看下keealived有没有检测到本机的mysql。（启动的时候先启动mysql在启动keepalived,要不mysql没起来启动keepalived会被脚本杀死。）

先看下mysql-ha1(192.168.5.234)

[root@mysql-ha1 ~] # service mysqld start
Starting MySQL.. SUCCESS!
[root@mysql-ha1 ~] # /etc/init.d/keepalived start
正在启动 keepalived：
[root@mysql-ha1 ~] # ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.5.55:mysql wrr persistent 50
  -> 192.168.5.234:mysql          Local   1      0          0

然后再看下mysql-ha1(192.168.5.155)

[root@mysql-ha2 ~] # service mysqld start
Starting MySQL.. SUCCESS!
[root@mysql-ha2 ~] # /etc/init.d/keepalived start
正在启动 keepalived：                                      [确定]
[root@mysql-ha2 ~] # ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  192.168.5.55:3306 wrr persistent 50
  -> 192.168.5.155:3306           Local   1      0          0

测试只开启mysql-ha1(192.168.5.234)mysql服务跟keepalived用客户端链接虚拟ip

[root@mysql-ha1 ~] # ps aux | grep keepalived
root      2977  0.0  0.0  41796   936 ?        Ss   23:14   0:00 keepalived -D
root      2978  0.0  0.1  43900  2156 ?        S    23:14   0:00 keepalived -D
root      2979  0.0  0.0  43900  1576 ?        S    23:14   0:00 keepalived -D
root      2982  0.0  0.0 103240   860 pts/0     S+   23:16   0:00  grep  keepalived
[root@mysql-ha1 ~] # netstat -ntlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program  name
tcp        0      0 0.0.0.0:3306                0.0.0.0:*                   LISTEN      2917/mysqld
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      1041/sshd
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      1416/master
tcp        0      0 0.0.0.0:5672                0.0.0.0:*                   LISTEN      1429/qpidd
tcp        0      0 :::22                       :::*                        LISTEN      1041/sshd
tcp        0      0 ::1:25                      :::*                        LISTEN      1416/master

mysql-ha2(192.168.5.155)

[root@mysql-ha2 ~] # ps aux | grep keepalived
root     10576  0.0  0.0   5980   756 pts/4     S+   15:24   0:00  grep  keepalived
[root@mysql-ha2 ~] # netstat -ntlp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       PID/Program  name
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      4776/sshd
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      1101/master
tcp        0      0 0.0.0.0:5672                0.0.0.0:*                   LISTEN      1114/qpidd
tcp        0      0 :::22                       :::*                        LISTEN      4776/sshd
tcp        0      0 ::1:25                      :::*                        LISTEN      1101/master

然后用客户端：192.168.5.10连接

C:\Users\Administrator>mysql -uduyunlong -p123456 -h192.168.5.55
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection  id  is 33
Server version: 5.5.22-log Source distribution
Type  'help;'  or  '\h'  for  help. Type  '\c'  to  clear  the buffer.
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
|  test                |
+--------------------+
4 rows  in  set  (0.02 sec)
mysql>

然后把mysql-ha1（192.168.5.234）mysql服务关掉，开启mysql-ha2(192.168.5.155)上的mysql服务跟keepalived。然后不退出mysql，继续查看数据库：

mysql-ha1(192.168.5.234)

[root@mysql-ha1 ~] # service mysqld stop
Shutting down MySQL... SUCCESS!

mysql-ha2(192.168.5.155)

[root@mysql-ha2 ~] # service mysqld start
Starting MySQL.. SUCCESS!
[root@mysql-ha2 ~] # /etc/init.d/keepalived start
正在启动 keepalived：                                      [确定]
[root@mysql-ha2 ~] #

客户端：192.168.5.10

mysql> show databases;
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection  id :    4
Current database: *** NONE ***
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
|  test                |
+--------------------+
4 rows  in  set  (0.01 sec)
mysql>

切换很快，大概在2到3秒之间！

利用LVS+Keepalived实现MySQL高可用

MySQL架构

MySQL的高可用，由一对互为主从的MySQL服务器组成，平时只有主库提供服务，备库不提供服务。当主库停止服务时，服务自动切换到备库。主备库通过双向复制，保证数据一致性。主备库以VIP对外统一服务接口。

Keepalived

MySQL对外服务接口的VIP，由Keepalived来实现心跳检查和动态漂移。因此MySQL和Keepalived部署在同一台服务器上，每台Keepalived配置的realserver即自身机器的MySQL服务。

环境安装

MySQL安装

两台服务器都安装MySQL，搭建主主复制架构。具体搭建略。

LVS+Keepalived安装

LVS源码安装

1. ln -s /usr/src/kernels/2.6.32-279.14.1.el6.x86_64/ /usr/src/linux
2. tar zxvf ipvsadm-1.24.tar.gz
3. cd ipvsadm-1.24
4. make && make install

Keepalived源码安装

安装依赖包

yum -y install popt-devel

安装Keepalived

点击(此处)折叠或打开

1. tar zxvf keepalived-1.1.19.tar.gz
2. cd keepalived-1.1.19
3. ./configure --prefix=/usr/local/keepalived
4. make && make install
5. cp /usr/local/keepalived/sbin/keepalived /usr/sbin/
6. cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/
7. cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/
8. mkdir /etc/keepalived

添加自启动

mysqld和keepalived自启动

点击(此处)折叠或打开

1. chkconfig --add mysqld
2. chkconfig --add keepalived
3. chkconfig mysqld on
4. chkconfig keepalived on

Keepalived配置

IP配置

这里的主备库IP配置如下

库	IP	服务VIP
主	10.0.0.77	10.0.0.76
备	10.0.0.78

Keepalived配置文件keepalived配置文件/etc/keepalived/keepalived.conf，主库为例

点击(此处)折叠或打开

1. global_defs {
2.    router_id LVS_1
3. }
4. vrrp_sync_group test {
5.    group {
6.      mysql_ha
7.    }
8. }
9. 
   
10. vrrp_instance mysql_ha {
11.    state BACKUP ## 主备库都是BACKUP，防止主库重启后，抢夺VIP资源
12.    interface eth0 ## HA地址网卡
13.    virtual_router_id 61
14.    priority 150 ## 优先级，主库比备库高
15.    nopreempt ## 非抢夺，在主库上配置，表示不抢夺VIP
16.    advert_int 1 ## 主备心跳检查间隔
17.    authentication {
18.      auth_type PASS
19.      auth_pass 1111
20.    }
21.    virtual_ipaddress { ## VIP，主备库一样
22.       10.0.0.76
23.    }
24.    ## 以下脚本是Keepalived改变状态时触发的动作，分别是变为backup、master、fault状态
25.    ## 这是个简单的报警脚本而已
    
26.    notify_backup "/usr/local/keepalived_script/keepalived_notify.sh BACKUP"
27.    notify_master "/usr/local/keepalived_script/keepalived_notify.sh MASTER"
28.    notify_fault "/usr/local/keepalived_script/keepalived_notify.sh FAULT"
29.    notify "/usr/local/keepalived_script/keepalived_notify.sh "
30. }
31. virtual_server 10.0.0.76 3306 {
32.    delay_loop 2
33.    lb_algo rr
34.    lb_kind DR
35.    persistence_timeout 20
36.    protocol TCP
37.    real_server 10.0.0.77 3306 { ## keepalived的realserver，主备库都取自身的mysql服务
38.      weight 3
39.      notify_down "/usr/local/keepalived_script/keepalived_notify.sh MYSQL_DOWN" ## 检测到realserver服务不可用时的动作
40.      TCP_CHECK {
41.        connect_timeout 3
42.        nb_get_retry 3
43.        delay_before_retry 3
44.        connect_port 3306
45.      }
46.    }
47. }

测试

测试效果

从以下4个方面测试HA效果
    keepalived down
    mysqld down
    网络故障
    机器宕机

测试步骤和结果

keepalived down

步骤：kill master上的keepalived进程

结果：

>>slave的keepalived通知切换为master

mysqld down

步骤：kill master上的mysqld进程，或者提高master服务器的负载

结果：

>>master的keepalived通知因为mysqld down而停止keepalived

>>slave的keepalived通知切换为master

网络故障

步骤：master上ifconfig eth0 down，或者service network restart

结果：

>>master的keepalived通知变为fault状态

>>slave的keepalived通知切换为master

 

机器宕机

步骤：master机器重启

结果：

>>slave的keepalived通知切换为master

问题分析

1，keepalived切换为master时，arping失败

有的环境测试，keepalived切换为master时，没有成功发送arping，导致VIP不同。所以给出了arping脚本

2，重启网卡，master变为fault状态，但没继续变为backup状态。

检查日志发现有错误信息

Keepalived_vrrp: Netlink: filter function error

Keepalived_healthcheckers: Netlink: filter function error

查找网络资料得知，keepalive不支持网络设备热插拔。ip link可以看出设备id变化了。

此时需要reload keepalived或者直接restart。

办法：网卡发生重启后，需检查keepalived是否正常

3，keepalived异常终止，VIP没有解除绑定，导致及时重启keepalived后，这个VIP也不能正常绑定和解除绑定

猜测原因是异常终止keepalived后，VIP没解除绑定，重启以后keepalived不识别未解除绑定的VIP。

办法：机器发生重启后需检查keepalived是否正常

4，ipvsadm使用yum安装，keepalived使用源码安装，keepalived不能启动healthchecker进程

keepalived安装时指定kernel目录：./configure --prefix=/usr/local/keepalived --with-kernel-dir=/usr/src/kernels/2.6.18-308.1.1.el5-x86_64

5，关于virtual_router_id

virtual_router_id用来标识一对keepalived主从机的身份，不同keepalived对的这个id不能一样。取值范围1~255。如果不同组keepalived配置了同一个id，则会有如下报错：

Apr  7 14:31:11 localhost Keepalived_vrrp[22980]: ip address associated with VRID not present in received packet : 10.0.0.94 Apr  7 14:31:11 localhostKeepalived_vrrp[22980]: one or more VIP associated with VRID mismatch actual MASTER advert Apr  7 14:31:11 localhost Keepalived_vrrp[22980]: bogus VRRP packet received on eth0.181 !!! Apr  7 14:31:11 localhost Keepalived_vrrp[22980]:  ------------- 使用keepalived搭建mysql主从备份、切换 2013-09-12 15:11:59 标签： mysql  keepalived  主从切换  master/master 原创作品，允许转载，转载时请务必以超链接形式标明文章  原始出处 、作者信息和本声明。否则将追究法律责任。 http://liuping0906.blog.51cto.com/2516248/1295092 mysql master/slave结构最大的缺点：当master宕机时不能切换到slave，这样就影响了业务的运行。为了弥补这个缺陷，我采用了keepalived+master/master结构。如图： 关于mysql的配置请参考：http://liuping0906.blog.51cto.com/2516248/879877 安装keepalived tar zxf keepalived- 1.2 . 8 .tar.gz cd keepalived- 1.2 . 8 ./configure --prefix=/opt/app/keepalived- 1.2 . 8 make make install 在192.168.110.128上配置文件keepalived.conf ! Configuration File for keepalived global_defs { router_id MYSQL-HA } vrrp_instance keepalive_mysql { state MASTER interface eth0 virtual_router_id 51 priority 100 advert_int 1 preempt authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168 . 110.8 / 24 } } 在192.168.110.137上配置文件keepalived.conf ! Configuration File for keepalived global_defs { router_id MYSQL-HA } vrrp_instance keepalive_mysql { state BACKUP interface eth0 virtual_router_id 51 priority 99 advert_int 1 nopreempt authentication { auth_type PASS auth_pass 1111 } virtual_ipaddress { 192.168 . 110.8 / 24 } } 说明： 配置上注意priority的值，192.168.110.128是master，优先级要高。 preempt表示抢占服务，当192.168.110.128恢复后，重新把服务抢过来。 keepalived默认网卡eth0和自身服务出现问题时才会切换。 通过编写脚本来监控mysql的状态进而控制keeepalived服务 #!/bin/bash MYSQL= "/usr/bin/mysql" MYSQL_HOST= 127.0 . 0.1 MYSQL_USER=admin MYSQL_PASSWORD=admin LOG_FILE= "/opt/app/keepalived/check_mysql.log" MYSQL_OK= 1 # mysql is working MYSQL_OK is 1 , mysql down MYSQL_OK is 0 check_mysql_helth() { $MYSQL -h$MYSQL_HOST -u$MYSQL_USER -p${MYSQL_PASSWORD} -e "show status" &>/dev/ null if [ $? = 0 ] ; then MYSQL_OK= 1 else MYSQL_OK= 0 fi return $MYSQL_OK } while : do CHECK_TIME= 3 while [ $CHECK_TIME -ne 0 ] do let "CHECK_TIME -= 1" check_mysql_helth [ $MYSQL_OK == 1 ] && break if [ $MYSQL_OK -eq 0 ] && [ $CHECK_TIME -eq 0 ]; then pkill keepalived echo `date --date=today + "%Y-%M-%d %H:%m:%S" ` - [INFO] - mysql invaild. keepalived stop. >> $LOG_FILE fi done done 说明： 通过监控mysql服务状态来控制keepalived服务，这里mysql停掉则kill掉keepalived。 分别在两台机器上执行下面命令 shell> /opt/app/keepalived/sbin/keepalived -f \ /opt/app/keepalived/etc/keepalived/keepalived .conf -D shell> nohup sh /opt/app/keepalived/bin/check_mysql .sh & 把第二条命令写入/etc/rc.local。 测试： > ip addr >killall mysqld 查看192.168.110.137 此时192.168.110.137充当临时服务器。 恢复192.168.110.128上的业务后查看 此时业务被192.168.110.128抢占过来，192.168.110.137充当备份、临时服务器。 遗留的问题： 1、本来在keepalived使用vrrp_script和strack_script来监控这个脚本，但是测试过几遍脚本都不运行。网上很多人都谈到这个问题，我不知道其他人怎么成功的。 2、当写入数据时主服务器宕机，从服务器来不及同步数据。此时造成用户数据写入但不能读取。缓解这个问题可以采用同步或者半同步。 3、主从切换时会造成业务闪断。 4、对于第一个问题可以结合lvs来解决。 5、主键冲突问题 参考文档 http://bbs.ywlm.net/thread-855-1-1.html http://bbs.ywlm.net/thread-845-1-1.html http://bbs.ywlm.net/thread-790-1-1.html - VRRP_Instance(mysql_ha) ignoring received advertisment...

6，端口转发

virtual_server配置的端口，与real_server配置的端口必须一样？