mysql双主互从通过KeepAlived虚拟IP实现高可用

在mysql 双主互从的基础上，
架构图：

Keepalived有两个主要的功能：

• 提供虚拟IP，实现双机热备
• 通过LVS，实现负载均衡

安装

# 安装
yum -y install keepalived 
# 卸载
yum remove keepalived 

修改 keepalived 配置文件

cp /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.original
vi /etc/keepalived/keepalived.conf

master

keepalived.conf

global_defs {router_id LVS_1script_user root
}vrrp_script check_mysql_port {script "/etc/keepalived/check_mysql_port.sh"    # 脚本存放的位置interval 2     # 每隔两秒运行上一行脚本weight 2
}vrrp_instance VI_1 {# 主机=MASTER;备用机=BACKUPstate MASTER# 该实例绑定的网卡名称interface ens192# 保证主备节点一致virtual_router_id 148# 权重，master值 > backup值priority 100# 主备组播报发送间隔时间1秒advert_int 1# 认证权限密码，防止非法节点进入authentication {auth_type PASSauth_pass 1111}	# 虚拟出来的ip，可以有多个（vip）virtual_ipaddress {178.119.30.13}# 调用监控脚本track_script {check_mysql_port}
}

检测xxx.sh

check_mysql_port.sh

安装killall 命令

# 查询
yum search killall
# 安装对应组件
yum install psmisc -y

安装netstat

yum install -y net-tools

#!/bin/bash
A=`netstat -nltp|grep 3306|wc -l`
if [ $A -eq 2 ];
thenecho "$host mysql login successfully"exit 0
elseecho "mysql login failed"killall keepalivedexit 2
fi

修改脚本xxx.sh权限

chmod 777 check_mysql_port.sh

slave

keepalived.conf

global_defs {router_id LVS_1script_user root
}vrrp_script check_mysql_port {script "/etc/keepalived/check_mysql_port.sh"    # 脚本存放的位置interval 2     # 每隔两秒运行上一行脚本weight 2
}vrrp_instance VI_1 {# 主机=MASTER;备用机=BACKUPstate BACKUP# 该实例绑定的网卡名称interface ens192# 保证主备节点一致virtual_router_id 148# 权重，master值 > backup值priority 80# 主备组播报发送间隔时间1秒advert_int 1# 认证权限密码，防止非法节点进入authentication {auth_type PASSauth_pass 1111}	# 虚拟出来的ip，可以有多个（vip）virtual_ipaddress {178.119.30.13}# 调用监控脚本track_script {check_mysql_port}
}

master VS slave

结果展示

启动keepalived

• master

• slave

停止容器，使vip飘移

• master
  
  
• slave
  
  

systemctl 命令

# 启动 keepalived
systemctl start keepalived  # 加入开机启动 keepalived
systemctl enable keepalived # 重新启动 keepalived
systemctl restart keepalived  # 查看 keepalived 状态
systemctl status keepalived   # 加载配置文件
systemctl daemon-reload

service VS systemctl