背景知识：
keepalived：Keepalived的作用是检测web服务器的状态，如果有一台web服务器死机，或工作出现故障，Keepalived将检测到，并将有故障的web 服务器从系统中剔除，当web服务器工作正常后Keepalived自动将web服务器加入到服务器群中，这些工作全部自动完成，不需要人工干涉，需要人工做的只是修复故障的web服务器。
LVS：LVS是Linux Virtual Server的简写，意即Linux虚拟服务器，是一个虚拟的服务器集群系统。
实验系统：CentOS 6.6_x86_64
实验前提：提前准备好编译环境，防火墙和selinux都关闭
实验说明：本实验共有4台主机，其中keep1和keep2为2台前端的keepalived服务器，real1和real2为LVS中的realserver，IP地址对应如拓扑图。
实验软件：httpd-2.2.15 keepalived-1.2.19
实验拓扑：
一、配置realserver
1.安装httpd：
yum -y install httpd
2.配置内核参数：
echo 1 > /proc/sys/net/ipv4/conf/lo/arp_ignore //仅在请求的地址配置在请求报文的接口进行响应 echo 1 > /proc/sys/net/ipv4/conf/all/arp_ignore echo 2 > /proc/sys/net/ipv4/conf/lo/arp_announce //表示仅通告网络直连的接口的地址 echo 2 > /proc/sys/net/ipv4/conf/all/arp_announce
3.增加测试页面并配置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、安装并配置keepalived
1.编译安装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/ //内核版本换成自己主机的 make && make install chkconfig --add keepalived chkconfig keepalived on
yum -y install ipvsadm //安装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 //调度类型 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
} } }
3.两台机器启动keepalived：
service keepalived start ipvsadm -L -n //用LVS工具查看keepalived运行 ip addr show //查看VIP
两台机器上LVS规则都已经生效，且2个VIP分别运行在2个节点：
keep1上：
keep2上：
分别打开测试页面进行测试：
停掉任何一个节点，资源都会自动转移：
至此，演示完毕，谢谢！如有问题，请与我联系，QQ：82800452