背景知識：

　　keepalived：Keepalived的作用是檢測web服務器的狀態，如果有一臺web服務器死機，或工作出現故障，Keepalived將檢測到，并將有故障的web 服務器從系統中剔除，當web服務器工作正常后Keepalived自動將web服務器加入到服務器群中，這些工作全部自動完成，不需要人工干涉，需要人工做的只是修復故障的web服務器。

　　LVS：LVS是linux Virtual Server的簡寫，意即Linux虛擬服務器，是一個虛擬的服務器集群系統。

實驗系統：CentOS 6.6_x86_64

實驗前提：提前準備好編譯環境，防火墻和selinux都關閉

實驗說明：本實驗共有4臺主機，其中keep1和keep2為2臺前端的keepalived服務器，real1和real2為LVS中的realserver，ip地址對應如拓撲圖。

實驗軟件：httpd-2.2.15　keepalived-1.2.19

實驗拓撲：

一、配置realserver

　　1.安裝httpd：

yum -y install httpd

　　2.配置內核參數：

echo 1 > /PRoc/sys/net/ipv4/conf/lo/arp_ignore           //僅在請求的地址配置在請求報文的接口進行響應echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignoreecho 2 > /proc/sys/net/ipv4/conf/lo/arp_announce         //表示僅通告網絡直連的接口的地址echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce

　　3.增加測試頁面并配置VIP：

　　　　real1上：

ifconfig lo:0 192.168.19.150 netmask 255.255.255.255 broadcast 192.168.19.150 up    //配置VIPifconfig lo:1 192.168.19.151 netmask 255.255.255.255 broadcast 192.168.19.151 uproute add -host 192.168.19.150 dev lo:0                                             //配置路由route add -host 192.168.19.151 dev lo:1vim /var/www/html/index.html---------------------------------------------<h1>realserver1</h1>---------------------------------------------service httpd start

　　　　real2上：

ifconfig lo:0 192.168.19.150 netmask 255.255.255.255 broadcast 192.168.19.150 upifconfig lo:1 192.168.19.151 netmask 255.255.255.255 broadcast 192.168.19.151 uproute add -host 192.168.19.150 dev lo:0route add -host 192.168.19.151 dev lo:1vim /var/www/html/index.html---------------------------------------------<h1>realserver2</h1>---------------------------------------------service httpd start

二、安裝并配置keepalived

　　1.編譯安裝keepalived，在keep1和keep2上操作：

wget http://www.keepalived.org/software/keepalived-1.2.19.tar.gztar xf keepalived-1.2.19.tar.gz cd keepalived-1.2.19./configure --prefix=/usr/local/keepalived --sbindir=/usr/sbin/ --sysconfdir=/etc/ --mandir=/usr/local/share/man/ --with-kernel-dir=/usr/src/kernels/2.6.32-504.30.3.el6.x86_64/      //內核版本換成自己主機的make && make installchkconfig --add keepalivedchkconfig keepalived onyum -y install ipvsadm                //安裝LVS工具

　　2.配置keepalived：

　　　　keep1上：

vim /etc/keepalived/keepalived.conf----------------------------------------------------vrrp_instance VI_1 {    state MASTER    interface eth0    virtual_router_id 31    priority 100    advert_int 1    authentication {        auth_type PASS        auth_pass abcd    }    virtual_ipaddress {        192.168.19.150    }}vrrp_instance VI_2 {    state BACKUP    interface eth0    virtual_router_id 41    priority 99    advert_int 1    authentication {        auth_type PASS        auth_pass abcd    }    virtual_ipaddress {        192.168.19.151    }}virtual_server 192.168.19.150 80 {    delay_loop 6    lb_algo rr                         //LVS算法    lb_kind DR                         //調度類型    protocol TCP    real_server 192.168.19.29 80 {            weight 1　　　　　　  inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }    real_server 192.168.19.34 80 {            weight 1　　　　　　  inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }}virtual_server 192.168.19.151 80 {    delay_loop 6    lb_algo rr    lb_kind DR    protocol TCP    real_server 192.168.19.29 80 {            weight 1　　　　　　  inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }    real_server 192.168.19.34 80 {            weight 1　　　　　　  inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }}

　　　　keep2上：

vim /etc/keepalived/keepalived.conf ----------------------------------------------

vrrp_instance VI_1 {    state BACKUP    interface eth0    virtual_router_id 31    priority 99    advert_int 1    authentication {        auth_type PASS        auth_pass abcd    }    virtual_ipaddress {        192.168.19.150    }}vrrp_instance VI_2 {    state MASTER    interface eth0    virtual_router_id 41    priority 100    advert_int 1    authentication {        auth_type PASS        auth_pass abcd    }    virtual_ipaddress {        192.168.19.151    }}virtual_server 192.168.19.150 80 {    delay_loop 6    lb_algo rr    lb_kind DR    protocol TCP    real_server 192.168.19.29 80 {            weight 1            inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }    real_server 192.168.19.34 80 {            weight 1            inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }}virtual_server 192.168.19.151 80 {    delay_loop 6    lb_algo rr    lb_kind DR    protocol TCP    real_server 192.168.19.29 80 {            weight 1            inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }    real_server 192.168.19.34 80 {            weight 1            inhibit_on_failure TCP_CHECK { connect_timeout 3 nb_get_retry 2 delay_before_retry 1 connect_port 80 }        }}

　　3.兩臺機器啟動keepalived：

service keepalived startipvsadm -L -n              //用LVS工具查看keepalived運行ip addr show               //查看VIP

　　　　兩臺機器上LVS規則都已經生效，且2個VIP分別運行在2個節點：

　　　　　　keep1上：

　　　　　　keep2上：

　　　　分別打開測試頁面進行測試：

　　　　停掉任何一個節點，資源都會自動轉移：

　　至此，演示完畢，謝謝！如有問題，請與我聯系，QQ：82800452