LVS,DR模式+Keepalived部署

配置信息

LVS-MASTER	10.0.0.41	centos7
LVS-BACKUP	10.0.0.42	centos7
LVS-DR-VIP	10.0.0.100
WEB1	10.0.0.43	centos7
WEB2	10.0.0.44	centos7

注意：請忽略IP地址，以自己環境中的爲主。
一、配置LVS
1.分別在lvs-master和lvs-backup上安裝lvs和keepalived軟件包

systemctl stop firewalld
setenforce 0
yum -y install keepalived ipvsadm

LVS-MASTER

vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id LVS_R1
}

vrrp_instance VI_1 {
    state MASTER
    interface ens33  #對應網卡
    virtual_router_id 51
    priority 100  #權重
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        10.0.0.100
    }
}

virtual_server 10.0.0.100 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
!    persistence_timeout 50
    protocol TCP

    real_server 10.0.0.43 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
            connect_port 80
        }
    }
    real_server 10.0.0.44 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
            connect_port 80
        }
    }
}

LVS-BACKUP

vi /etc/keepalived/keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id LVS_R2
}

vrrp_instance VI_1 {
    state BACKUP   
    interface ens33 
    virtual_router_id 51
    priority 99
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        10.0.0.100
    }
}

virtual_server 10.0.0.100 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
!    persistence_timeout 50
    protocol TCP

    real_server 10.0.0.43 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
            connect_port 80
        }
    }
    real_server 10.0.0.44 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
            connect_port 80
        }
    }
}

2、啓動lvs

systemctl restart keepalived

備keepalived配置文件配置信息：備用服務器可以有多臺，配置時候基本相同只要修改路由器名稱，熱備狀態，優先級就可以了。
二、.節點WEB1,WEB2服務器配置
1、使用DR模式的時候，節點服務器也需要配置vip地址，並且調整內核的ARP響應參數以阻止更新VIP的MAC地址，避免發生衝突。

cd /etc/sysconfig/network-scripts/
cp ifcfg-lo  ifcfg-lo:0
vi ifcfg-lo:0

ifup lo:0
ifconfig lo:0

添加VIP本地訪問路由（將訪問VIP的數據限制正在本地，避免通信紊亂）

 vi /etc/rc.local

執行

route add -host 10.0.0.100 dev lo:0

2、修改內核參數。

/etc/sysctl.conf（最下面添加）

echo 'net.ipv4.conf.all.arp_ignore = 1
net.ipv4.conf.all.arp_announce = 2
net.ipv4.conf.default.arp_ignore = 1
net.ipv4.conf.default.arp_announce = 2
net.ipv4.conf.lo.arp_ignore = 1
net.ipv4.conf.lo.arp_announce = 2' >>/etc/sysctl.conf

注意：
arp_announce爲2時：只向該網卡迴應與該網段匹配的ARP報文。
arp_ignore爲1：只響應目的IP地址爲接收網卡上的本地地址的arp請求
其主要是實現禁止響應ARP的請求。
3、啓動內核參數

sysctl  -p

4、2安裝httpd，創建網頁測試lvs集羣
WEB1

yum -y install  httpd
echo "WEB1" >/var/www/html/index.html
systemctl start httpd	

WEB2

yum -y install httpd
echo "WEB2" >/var/www/html/index.html
systemctl start httpd	

測試：

ipvsadm  -lnc

在沒有vip的服務curl一下，瀏覽器有緩存，就算開啓無痕也是一樣，要命令行curl