lvs+keepalived+nginx双主模式双主热备实现负载均衡

[3.1 配置文件](#3.1 配置文件)

[3.2 开启keepalived服务](#3.2 开启keepalived服务)

[4.1 测试访问VIP](#4.1 测试访问VIP)

[4.2 模拟lvs01宕机](#4.2 模拟lvs01宕机)

|---------|-----------|
| 主机名 | IP |
| nginx01 | 11.0.1.31 |
| nginx01 | 11.0.1.31 |
| lvs01 | 11.0.1.33 |
| lvs02 | 11.0.1.34 |
| VIP1 | 11.0.1.29 |
| VIP2 | 11.0.1.30 |

一、原理

lvs+keepalived+nginx主备模式下，lvs永远只有一台在工作，资源利用率并不高，双主模式可以解决这一问题。

确保真实IP11.0.1.31、11.0.1.32访问正常

二、真实服务器nginx配置

nginx01、nginx02 执行real_server.sh脚本

新建real_server.sh脚本并执行，脚本内容为lo网卡新增两个虚拟接口，添加linux内核路由，关闭arp功能。

[root@nginx01 ~]# cat /etc/keepalived/real_server.sh

ifconfig lo:0 11.0.1.29 netmask 255.255.255.255 broadcast 11.0.1.29
route add -host 11.0.1.29 dev lo:0

ifconfig lo:1 11.0.1.30 netmask 255.255.255.255 broadcast 11.0.1.30 
route add -host 11.0.1.30 dev lo:1
 
echo "1" >/proc/sys/net/ipv4/conf/lo/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/lo/arp_announce
echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce

[root@nginx01 ~]# chmod +x /etc/keepalived/real_server.sh

[root@nginx01 ~]# sh /etc/keepalived/real_server.sh

查看nginx01网卡信息

查看nginx02网卡信息

三、lvs的keepalived配置

3.1 配置文件

注意有两个VRRP实例，两个VIP，一个VRRP实例对应一个VIP

|-----------------------|----------------------------------|
| VRRP 1（VIP 11.0.1.29） | 11.0.1.33 master 11.0.1.34 slave |
| VRRP 2（VIP11.0.1.30） | 11.0.1.33 slave 11.0.1.34 master |

lvs01-33

[root@lvs01-33 ~]# cat /etc/keepalived/keepalived.conf
vrrp_instance VI_1 {
    state MASTER
    interface ens33
    virtual_router_id 31
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass abcd
    }
    virtual_ipaddress {
        11.0.1.29
    }
}

vrrp_instance VI_2 {
    state BACKUP
    interface ens33
    virtual_router_id 41
    priority 99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass abcd
    }
    virtual_ipaddress {
        11.0.1.30
    }
}

virtual_server 11.0.1.29 80 {
    delay_loop 6
    lb_algo rr                  
    lb_kind DR                     
    protocol TCP

    real_server 11.0.1.31 80 {
            weight 1　　　　　　  
			inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }

    real_server 11.0.1.32 80 {
            weight 1　　　　　　  
			inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }
}

virtual_server 11.0.1.30 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    protocol TCP

    real_server 11.0.1.31 80 {
            weight 1　　　　　　  
			inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }

    real_server 11.0.1.32 80 {
            weight 1　　　　　　  
			inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }
}

lvs02-34

[root@lvs02-34 ~]# cat /etc/keepalived/keepalived.conf
vrrp_instance VI_1 {
    state BACKUP
    interface ens33
    virtual_router_id 31
    priority 99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass abcd
    }
    virtual_ipaddress {
        11.0.1.29
    }
}

vrrp_instance VI_2 {
    state MASTER
    interface ens33
    virtual_router_id 41
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass abcd
    }
    virtual_ipaddress {
        11.0.1.30
    }
}

virtual_server 11.0.1.29 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    protocol TCP

    real_server 11.0.1.31 80 {
            weight 1
            inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }

    real_server 11.0.1.32 80 {
            weight 1
            inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }
}

virtual_server 11.0.1.30 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    protocol TCP

    real_server 11.0.1.31 80 {
            weight 1
            inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }

    real_server 11.0.1.32 80 {
            weight 1
            inhibit_on_failure            
			TCP_CHECK {            
			connect_timeout 3            
			nb_get_retry 2            
			delay_before_retry 1            
			connect_port 80            
			}
        }
}