Keepalived+LVS(DR)+MySQL

实验环境

主机名	IP	VIP	服务	主备
KA_LV_MYSQL_01	192.168.30.130	192.168.30.100	keepalived、LVS、MySQL	MASTER
KA_LV_MYSQL_02	192.168.30.131			BACKUP

软件版本：

[root@KA_LV_MYSQL_01 ~]# cat /etc/redhat-release
CentOS release 6.9 (Final)

[root@KA_LV_MYSQL_01 ~]# keepalived -v
Keepalived v1.2.13 (03/19,2015)
[root@KA_LV_MYSQL_01 ~]# mysql -V
mysql Ver 14.14 Distrib 5.1.73, for redhat-linux-gnu (x86_64) using readline 5.1
[root@KA_LV_MYSQL_01 ~]# ipvsadm -v
ipvsadm v1.26 2008/5/15 (compiled with popt and IPVS v1.2.1)

安装：

配置好本地YUM源，直接采用光盘镜像中的软件进行安装。

[root@KA_LV_MYSQL_01 ~]# yum install -y mysql mysql-server keepalived ipvsadm

配置MySQL主从：

[root@KA_LV_MYSQL_01 ~]# cp /etc/my.cnf{,.bak}

[root@KA_LV_MYSQL_01 ~]# vim /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-bin=mysql-master-bin                            
server-id=1
binlog-ignore-db=mysql                             #忽略这些库
binlog-ignore-db=user                               
binlog-ignore-db=information_schema

值得注意的是：需要忽略哪些数据库时有三种方法：

.在主节点上的/etc/my.cnf中使用binlog-do-db、binlog-ignore-db参数指定。
.在使用grant指定权限时，指定数据库
.在slave上限定数据库使用replicate-do-db=dbname

[root@KA_LV_MYSQL_01 ~]# mysql -uroot -p123456

Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 754
Server version: 5.1.73-log Source distribution

Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> grant replication client,replication slave on *.* to root@'192.168.30.%' identified by '123456';

mysql> grant all privileges on *.* to root@'%' identified by '123456' with grant option;

mysql> flush privileges;

mysql> show binary logs;
+-------------------------+-----------+
| Log_name | File_size |
+-------------------------+-----------+
| mysql-master-bin.000001 | 19726 |
| mysql-master-bin.000002 | 765307 |
| mysql-master-bin.000003 | 125 |
| mysql-master-bin.000004 | 276 |
+-------------------------+-----------+
4 rows in set (0.00 sec)

mysql> reset master;
Query OK, 0 rows affected (0.02 sec)

mysql> show binary logs;
+-------------------------+-----------+
| Log_name | File_size |
+-------------------------+-----------+
| mysql-master-bin.000001 | 106 |
+-------------------------+-----------+
1 row in set (0.00 sec)

配置mysql从节点

[root@KA_LV_MYSQL_02 ~]# vim /etc/my.cnf
[mysqld]
datadir=/var/lib/mysql
socket=/var/lib/mysql/mysql.sock
log-bin=mysql-slave-bin
server-id=2

mysql> change master to

-> master_host='192.168.30.130',
-> master_user='root',
-> master_password='123456',
-> master_log_file='mysql-master-bin.000001',
-> master_port=3306,
-> master_log_pos=106;
Query OK, 0 rows affected (0.02 sec)

mysql> start slave;
Query OK, 0 rows affected (0.00 sec)

mysql> show slave status \G;
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.30.130
Master_User: root
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-master-bin.000001
Read_Master_Log_Pos: 106
Relay_Log_File: mysqld-relay-bin.000002
Relay_Log_Pos: 258
Relay_Master_Log_File: mysql-master-bin.000001
Slave_IO_Running: Yes            #这两个Yes说明mysql主从配置成功
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 106
Relay_Log_Space: 414
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
1 row in set (0.00 sec)

ERROR:
No query specified

配置keepalived：

[root@KA_LV_MYSQL_01 ~]# cp /etc/keepalived/keepalived.conf{,.bak}

[root@KA_LV_MYSQL_01 ~]# vim /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
notification_email {
　　1255560195@qq.com
}
notification_email_from 1255560195@qq.com
　　smtp_server 127.0.0.1
　　smtp_connect_timeout 30
　　router_id KA_LV_MYSQL_01
}

vrrp_instance VI_1 {
　　state MASTER
　　interface eth0
　　virtual_router_id 51
　　priority 200

　　advert_int

 authentication {
      auth_type PASS
      auth_pass
    }
    virtual_ipaddress {
        192.168.30.100

    }
}

virtual_server 192.168.30.100  {
    delay_loop
    lb_algo wlc
    lb_kind DR
    nat_mask 255.255.255.0
    persistence_timeout
    protocol TCP

    real_server 192.168.30.130  {
        weight
        TCP_CHECK {
            connect_timeout
            nb_get_retry
            delay_before_retry
            connect_port
        }
    }
    real_server 192.168.30.131  {
        weight
        TCP_CHECK {
            connect_timeout
            nb_get_retry
            delay_before_retry
            connect_port
        }
    }
}

在KA_LV_MYSQL_02上只需修改如下两个地方即可。

router_id KA_LV_MYSQL_02

priority 100

配置LVS

[root@KA_LV_MYSQL_01 network-scripts]# cp ifcfg-lo ifcfg-lo:1
[root@KA_LV_MYSQL_01 network-scripts]# vim ifcfg-lo:1
DEVICE=lo:1
IPADDR=192.168.30.100
NETMASK=255.255.255.255
#NETWORK=
# If you're having problems with gated making 127.0.0.0/8 a martian,
# you can change this to something else (255.255.255.255, for example)
BROADCAST=192.168.30.100
ONBOOT=yes
NAME=loopback

[root@KA_LV_MYSQL_01 network-scripts]# service network restart

[root@KA_LV_MYSQL_01 ~]# service ipvsadm restart && service keepalived restart

[root@KA_LV_MYSQL_01 network-scripts]# chkconfig ipvsadm on
[root@KA_LV_MYSQL_01 network-scripts]# chkconfig keepalived on
[root@KA_LV_MYSQL_01 network-scripts]# ipvsadm -A -t 192.169.30.100:3306 -s wlc
[root@KA_LV_MYSQL_01 network-scripts]# ipvsadm -a -t 192.168.30.100:3306 -r 192.168.30.130 -g
Destination already exists
[root@KA_LV_MYSQL_01 network-scripts]# ipvsadm -a -t 192.168.30.100:3306 -r 192.168.30.131 -g
Destination already exists
[root@KA_LV_MYSQL_01 network-scripts]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.30.100:3306 wlc persistent 50
-> 192.168.30.130:3306 Local 3 0 0
-> 192.168.30.131:3306 Route 3 0 0
TCP 192.169.30.100:3306 wlc

在KA_LV_MYSQL_02上做相应操作即可。

测试：

在KA_LV_MYSQL_01上登入MySQL

在KA_LV_MYSQL_02上登入MySQL并查看

手动停掉KA_LV_MYSQL_02上的MySQL，去KA_LV_MYSQL_01上查看日志如下，可以看出，当停掉MySQL时，keepalived可以将故障节点自动剔除，当故障节点恢复时，又会重新加入到集群中。 

[root@KA_LV_MYSQL_01 network-scripts]# tail /var/log/messages
Apr 25 08:12:43 KA_LV_MYSQL_01 Keepalived_vrrp[70845]: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.30.100
Apr 25 08:12:48 KA_LV_MYSQL_01 Keepalived_vrrp[70845]: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.30.100
Apr 25 08:16:15 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: TCP connection to [192.168.30.131]:3306 failed !!!
Apr 25 08:16:15 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: Removing service [192.168.30.131]:3306 from VS [192.168.30.100]:3306
Apr 25 08:16:15 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: Remote SMTP server [127.0.0.1]:25 connected.
Apr 25 08:16:15 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: SMTP alert successfully sent.
Apr 25 08:18:45 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: TCP connection to [192.168.30.131]:3306 success.
Apr 25 08:18:45 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: Adding service [192.168.30.131]:3306 to VS [192.168.30.100]:3306
Apr 25 08:18:45 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: Remote SMTP server [127.0.0.1]:25 connected.
Apr 25 08:18:45 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: SMTP alert successfully sent.

手动关掉KA_LV_MYSQL_01上的keepalived，查看主备节点日志日志，可以看出，KA_LV_MYSQL_02已经接变成master，并接管了VIP。

[root@KA_LV_MYSQL_01 ~]# tail /var/log/messages
Apr 25 09:09:49 KA_LV_MYSQL_01 Keepalived[70843]: Stopping Keepalived v1.2.13 (03/19,2015)
Apr 25 09:09:49 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: Removing service [192.168.30.130]:3306 from VS [192.168.30.100]:3306
Apr 25 09:09:49 KA_LV_MYSQL_01 Keepalived_vrrp[70845]: VRRP_Instance(VI_1) sending 0 priority
Apr 25 09:09:49 KA_LV_MYSQL_01 Keepalived_healthcheckers[70844]: Removing service [192.168.30.131]:3306 from VS [192.168.30.100]:3306
Apr 25 09:09:49 KA_LV_MYSQL_01 Keepalived_vrrp[70845]: VRRP_Instance(VI_1) removing protocol VIPs.
Apr 25 09:09:49 KA_LV_MYSQL_01 kernel: IPVS: __ip_vs_del_service: enter

[root@KA_LV_MYSQL_02 ~]# tail /var/log/messages
Apr 25 09:09:50 KA_LV_MYSQL_02 Keepalived_vrrp[6325]: VRRP_Instance(VI_1) Transition to MASTER STATE
Apr 25 09:09:51 KA_LV_MYSQL_02 Keepalived_vrrp[6325]: VRRP_Instance(VI_1) Entering MASTER STATE
Apr 25 09:09:51 KA_LV_MYSQL_02 Keepalived_vrrp[6325]: VRRP_Instance(VI_1) setting protocol VIPs.
Apr 25 09:09:51 KA_LV_MYSQL_02 Keepalived_vrrp[6325]: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.30.100
Apr 25 09:09:51 KA_LV_MYSQL_02 Keepalived_healthcheckers[6324]: Netlink reflector reports IP 192.168.30.100 added
Apr 25 09:09:56 KA_LV_MYSQL_02 Keepalived_vrrp[6325]: VRRP_Instance(VI_1) Sending gratuitous ARPs on eth0 for 192.168.30.100

KA_LV_MYSQL_02上的LVS集群正常。

[root@KA_LV_MYSQL_02 ~]# ipvsadm -ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
-> RemoteAddress:Port Forward Weight ActiveConn InActConn
TCP 192.168.30.100:3306 wlc persistent 50
-> 192.168.30.130:3306 Route 3 0 0
-> 192.168.30.131:3306 Local 3 0 0