背景知識：
keepalived：Keepalived的作用是檢測web服務器的狀態，如果有一台web服務器死機，或工作出現故障，Keepalived將檢測到，並將有故障的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：提前准備好編譯環境，防火牆和selinux都關閉
實驗說明：本實驗共有4台主機，其中keep1和keep2為2台前端的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_ignore echo 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.增加測試頁面並配置VIP：
real1上：
ifconfig lo:0 192.168.19.150 netmask 255.255.255.255 broadcast 192.168.19.150 up //配置VIP
ifconfig lo:1 192.168.19.151 netmask 255.255.255.255 broadcast 192.168.19.151 up
route add -host 192.168.19.150 dev lo:0 //配置路由
route add -host 192.168.19.151 dev lo:1 vim /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 up
ifconfig lo:1 192.168.19.151 netmask 255.255.255.255 broadcast 192.168.19.151 up
route add -host 192.168.19.150 dev lo:0
route add -host 192.168.19.151 dev lo:1 vim /var/www/html/index.html --------------------------------------------- <h1>realserver2</h1> --------------------------------------------- service httpd start
二、安裝並配置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.gz
tar 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 install chkconfig --add keepalived chkconfig keepalived on
yum -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
} } }
3.兩台機器啟動keepalived：
service keepalived start ipvsadm -L -n //用LVS工具查看keepalived運行 ip addr show //查看VIP
兩台機器上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