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MySQL+Keepalived实验指导
Keepalived+mysql 自动切换
项目环境：
VIP 192.168.246.100
mysql1 192.168.246.162 keepalived-master
mysql2 192.168.246.163 keepalived-salve
一、mysql 主主同步 （不使用共享存储，数据保存本地存储）
二、安装keepalived
三、keepalived 主备配置文件
四、mysql状态检测脚本/root/bin/keepalived_check_mysql.sh
五、测试及诊断
实施步骤：
一、mysql 主主同步
二、安装keepalived---两台机器都操作
[root@mysql-keepalived-master ~]# yum -y install keepalived
[root@mysql-keepalived-slave ~]# yum -y install keepalived
三、keepalived 主备配置文件
192.168.246.162 master配置
[root@mysql-keepalived-master ~]# cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
[root@mysql-keepalived-master ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
router_id master
}
vrrp_script check_run {
script "/etc/keepalived/keepalived_chech_mysql.sh"
interval 5
}
vrrp_instance VI_1 {
state MASTER
interface ens33
virtual_router_id 89
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.246.100/24
}
track_script {
check_run
}
}
slave 192.168.246.163 配置
[root@mysql-keepalived-slave ~]# cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.bak
[root@mysql-keepalived-slave ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
router_id backup
}
vrrp_script check_run {
script "/etc/keepalived/keepalived_check_mysql.sh"
interval 5
}
vrrp_instance VI_1 {
state BACKUP
nopreempt
interface ens33
virtual_router_id 89
priority 50
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.246.100/24
}
track_script {
check_run
}
}
四、mysql状态检测脚本/root/keepalived_check_mysql.sh（两台MySQL同样的脚本）
版本一：简单使用：
[root@mysql-keepalived-master ~]# vim /etc/keepalived/keepalived_check_mysql.sh
#!/bin/bash
/usr/bin/mysql -uroot -p'QianFeng@2019!' -e "show status" &>/dev/null
if [ $? -ne 0 ] ;then
# service keepalived stop
systemctl stop keepalived
fi
[root@mysql-keepalived-master ~]# chmod +x /etc/keepalived/keepalived_check_mysql.sh
==========================================================================
两边均启动keepalived
方式一:
[root@mysql-keepalived-master ~]# systemctl start keepalived
[root@mysql-keepalived-master ~]# systemctl enable keepalived
方式二:
# /etc/init.d/keepalived start
# /etc/init.d/keepalived start
# chkconfig --add keepalived
# chkconfig keepalived on
注意:在任意一台机器作为客户端。在测试的时候记得检查mysql用户的可不可以远程登录。
MySQL+Keepalived实验操作
１、写在前面的说明：
这个实验只是熟练keepalived实现四层负载均衡的原理，真正的应用场景中不会给数据库做高可用，会给单一的入口节点Tomcat做高可用，此实验中没有用到负载均衡，两台服务区即可，为了验证ip偏移，就不做主从复制了。双主双从，互为主从的致命缺陷是：如果同一时间主服务器和从服务器后进行了同一个主键的记录的创建，那么在进行主从复制的过程中会相互报错，主键冲突。
２、sql-master的配置
数据库配置
yum -y install keepalived
yum -y install mariadb mariadb-server
systemctl start mariadb
mysqladmin password 123
mysql -uroot -p123
grant all on *.* to 'root'@'%' identified by '123';
flush privileges;
两个数据路中创建不同的库进行区分
create database db1;
高可用配置
vim /etc/keepalived/keepalived.conf
global_defs {
router_id master
}
vrrp_script check_run {
script "/etc/keepalived/keepalived_check_mysql.sh"
interval 5
}
vrrp_instance VI_1 {
state MASTER
interface ens37
virtual_router_id 89
priority 100
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.138.150/24
}
track_script {
check_run
}
}
３、sql-slave的配置
数据库配置
yum -y install keepalived
yum -y install mariadb mariadb-server
systemctl start mariadb
mysqladmin password 123
mysql -uroot -p123
grant all on *.* to 'root'@'%' identified by '123';
flush privileges;
两个数据路中创建不同的库进行区分
create database db2;
高可用配置
vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
router_id backup
}
vrrp_script check_run {
script "/etc/keepalived/keepalived_check_mysql.sh"
interval 5
}
vrrp_instance VI_1 {
state BACKUP
nopreempt
interface ens33
virtual_router_id 89
priority 50
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.138.150/24
}
track_script {
check_run
}
}
４、登录验证
[root@web-server1 ~]# mysql -p123 -h 192.168.138.150
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 10
Server version: 5.5.65-MariaDB MariaDB Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| db1 |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.00 sec)
可以看到，此时显示db1，说明登录了sql-master数据库服务器
把sql-master宕机测试
MariaDB [(none)]> show databases;
ERROR 2013 (HY000): Lost connection to MySQL server during query
MariaDB [(none)]> show databases;
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id: 4
Current database: *** NONE ***
+--------------------+
| Database |
+--------------------+
| information_schema |
| db2 |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.01 sec)
MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| db2 |
| mysql |
| performance_schema |
| test |
+--------------------+
5 rows in set (0.01 sec)
可以看到，还是进行数据库的切换，所以，高可用可用