Keepalived 实战示例看了就会配置（上）

今天给伙伴们分享一下Keepalived 实战示例（上），希望看了有所收获。

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一、Keepalived 实现 HA

• 注：主/备调度器均能够实现正常调度

1、主/备调度器安装软件

[root@edenluo-lb1 ~]# yum -y install keepalived 

2、Keepalived 配置

1、BACKUP1 配置

[root@edenluo-lb1 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   
   router_id director1		
}
vrrp_instance VI_1 {
   
    state MASTER
    nopreempt				    
    interface eth0				
    virtual_router_id 80		
    priority 100				
    advert_int 1
    authentication {
   
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
   
        192.168.152.100
    }
}

2、BACKUP2 配置

[root@edenluo-lb2 ~]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   
   router_id director2		    
}

vrrp_instance VI_1 {
   
    state BACKUP
    nopreempt				    
    interface eth0				
    virtual_router_id 80		
    priority 50				
    advert_int 1
    authentication {
   
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
   
        192.168.152.100
    }
}

3、启动KeepAlived（主备均启动）

[root@edenluo-lb1 ~]# systemctl enable keeplived
[root@edenluo-lb1 ~]# systemctl start keeplived
[root@edenluo-lb1 ~]# ip addr

• 到此：可以解决心跳故障 keepalived，不能解决Nginx服务故障

4、扩展对调度器Nginx健康检查（可选）

• 思路：让Keepalived以一定时间间隔执行一个外部脚本，脚本的功能是当Nginx失败，则关闭本机的Keepalived

1、nginx 检测脚本

[root@edenluo-lb1 ~]# cat /etc/keepalived/check_nginx_status.sh
#!/bin/bash												        
/usr/bin/curl -I http://localhost &>/dev/null	
if [ $? -ne 0 ];then										    
	systemctl stop keepalive					    	
fi															        	

[root@edenluo-lb1 ~]# chmod a+x /etc/keepalived/check_nginx_status.sh

2、keepalived 使用检测脚本

! Configuration File for keepalived

global_defs {
   router_id director1
}

vrrp_script check_nginx {
   script "/etc/keepalived/check_nginx_status.sh"
   interval 5
}

vrrp_instance VI_1 {
    state BACKUP
    interface eth0
    nopreempt
    virtual_router_id 90
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    track_script {
        check_nginx
    }
    virtual_ipaddress {
        192.168.152.100
    }
}

• 注：必须先启动nginx，再启动keepalived

二、Keepalived+LVS_Dr 高可用集群

1、KeepAlived 在该项目中的功能

• 管理IPVS的路由表（包括对RealServer做健康检查）
• 实现调度器的HA

2、获取组播信息

[root@mysql1 ~]# tcpd