Mysql + keepalive高可用搭建

               Mysql + keepalive高可用搭建

系統環境：centos6.8
Ip：192.168.137.36 主庫
192.168.137.38 從庫

VIP(虛擬ip/浮動ip):192.168.137.100

軟件版本：mysql 5.7.20
Keepalived 1.2.13

主從搭建略
Mysql1
vim /etc/my.cnf
binlog-do-db=test
log-bin=mysql-bin
server-id=1
gtid-mode=ON
enforce-gtid-consistency

Mysql2
Vim /etc/my.cnf
gtid-mode=ON
enforce-gtid-consistency
log-bin=mysql-bin
log-slave-updates=ON
server-id=3
binlog-do-db=test

安裝keepalived
yum install keepalived

在192.168.137.36主庫修改keepalived的配置文件
注意：加顏色部分為修改部分

[root@zabbix ~]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs{
notification_email {
root@localhost
}
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
#VIP1
vrrp_instance VI_1 {
state BACKUP
interface eth0
lvs_sync_daemon_inteface eth0
virtual_router_id 151
priority 100
advert_int 5
nopreempt
authentication {
auth_type PASS
auth_pass 2222
}
virtual_ipaddress {
192.168.137.100
}
}
virtual_server 192.168.137.100 3306 {
delay_loop 6
lb_algo wrr
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 192.168.137.36 3306 {
weight 100
notify_down /data/sh/mysql.sh
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
}

保存退出
在192.168.137.38從庫修改keepalived的配置文件
[root@localhost sh]# cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs{
notification_email {
root@localhost
}
smtp_server 127.0.0.1
smtp_connect_timeout 30
router_id LVS_DEVEL
}
#VIP1
vrrp_instance VI_1 {
state BACKUP
interface eth0
lvs_sync_daemon_inteface eth0
virtual_router_id 151
priority 98
advert_int 5
nopreempt
authentication {
auth_type PASS
auth_pass 2222
}
virtual_ipaddress {
192.168.137.100
}
}
virtual_server 192.168.137.100 3306 {
delay_loop 6
lb_algo wrr
lb_kind DR
persistence_timeout 60
protocol TCP
real_server 192.168.137.38 3306 {
weight 98
notify_down /data/sh/mysql.sh
TCP_CHECK {
connect_timeout 10
nb_get_retry 3
delay_before_retry 3
connect_port 3306
}
}
}
保存退出
上面的配置簡單說明：
state BACKUP??表示為備模式，nopreempt?為不搶占，雙方都配為備模式，并且不搶占，可以避免“腦裂”問題，priority 100?為權重，數字越高，權重越高，當雙方都配為BACKUP模式，并且配置nopreempt時，keepalived靠這個數字來判斷誰是主，誰是備
主從都要創建/data/sh/mysql.sh腳本
mkdir /data/sh
vim?/data/sh/mysql.sh?加入以下內容：
#！/bin/bash
/etc/init.d/keepalived? stop
?
chmod??755? /data/sh/mysql.sh
modprobe ?ip_vs??#加載ip_vs模塊?虛擬IP要用
lsmod?|? grep? ip_vs??查看ip_vs模塊有沒有加載，如果看到下面的內容，就表示加載成功：

/etc/init.d/mysqld? start??#啟動mysql
/etc/init.d/keepalive? start???#啟動keepalived
在36上的操作和38上一樣，只是keepalived.conf配置文件里priority 100?改為?priority 98
?
real_server 192.168.137.36?改為?real_server 192.168.137.38其他不變。
?
查看VIP情況命令: ip a

?
至此mysql的主從高可用就做好了，可以在36上測試挺掉mysql服務，看看vip會不會漂移到38上，一般來說都是沒問題的，如果有問題，請檢查你的配置，步驟是不是有錯誤，還有selinux，防火墻是否關閉等