lvs+keepalived高可用负载均衡

说明：
lvs+keepalived-master 172.16.0.111
lvs+keepalived-backup 172.16.0.112
web-1 172.16.0.113
web-2 172.16.0.114
VIP 172.16.0.100
lvs管理工具ipvsadm
keepalived-1.3.5.tar.gz

1.查看是否支持lvs

[root@lvs-master ~]# cat /boot/config-2.6.32-573.el6.x86_64 
[root@lvs-master ~]# modprobe -l |grep ipvs

2.lvs主备服务器安装keepalived

[root@lvs-master ~]# tar zxvf keepalived-1.3.5.tar.gz
[root@lvs-master ~]# cd keepalived-1.3.5
[root@lvs-master keepalived-1.3.5]# ./configure --prefix=/usr/local/keepalived
[root@lvs-master keepalived]# make && make install

3.配置keepalived用service命令启动

a.复制/sbin/keepalived到/usr/sbin下

[root@lvs-master ~]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/

b.复制sysconfig文件到/etc/sysconfig下

[root@lvs-master ~]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/

c.复制启动脚本到/etc/init.d下

[root@lvs-master ~]# cp  ~/keepalived-1.3.5/keepalived/etc/init.d/keepalived  /etc/init.d/

d.keepalived默认会读取/etc/keepalived/keepalived.conf配置文件

[root@lvs-master ~]# mkdir /etc/keepalived
[root@lvs-master ~]# cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf

4.编辑keepalived配置文件
a.主服务器上如下

[root@lvs-master keepalived-1.3.5]# vim /etc/keepalived/keepalived.conf
! Configuration File for keepalived

global_defs {
   notification_email {
     acassen@firewall.loc
     failover@firewall.loc
     sysadmin@firewall.loc
   }
   notification_email_from Alexandre.Cassen@firewall.loc
   smtp_server 192.168.200.1
   smtp_connect_timeout 30
   router_id LVS_DEVEL
   vrrp_skip_check_adv_addr
   vrrp_strict
   vrrp_garp_interval 0
   vrrp_gna_interval 0
}

vrrp_instance VI_1 {
    state MASTER
    interface eth0
    virtual_router_id 51
    priority 100
    advert_int 1
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        172.16.0.100
    }
}

virtual_server 172.16.0.100 80 {
    delay_loop 6
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 172.16.0.113 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 10
            nb_get_retry 3
            delay_before_retry 3
        }
    }
    real_server 172.16.0.114 80 {
        weight 1
        TCP_CHECK {
            connect_timeout 10
            nb_get_retry 3
            delay_before_retry 3
            connect_port 80
        }
    }
}

b.备服务器上配置文件做如下修改

state ------>BACKUP #与MASTER对应
priority ------>90  #小于100

c.启动

[root@lvs-master ~]# service keepalived start
[root@lvs-master ~]# chkconfig keepalived on

5.配置web服务器

[root@web-1 init.d]# vim /etc/init.d/realserver
#!/bin/bash
SNS_VIP=172.16.0.100
/etc/rc.d/init.d/functions
case "$1" in
start)
       ifconfig lo:0 $SNS_VIP netmask 255.255.255.255 broadcast $SNS_VIP
       /sbin/route add -host $SNS_VIP dev lo:0
       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
       sysctl -p >/dev/null 2>&1
       echo "RealServer Start OK"
       ;;
stop)
       ifconfig lo:0 down
       route del $SNS_VIP >/dev/null 2>&1
       echo "0" >/proc/sys/net/ipv4/conf/lo/arp_ignore
       echo "0" >/proc/sys/net/ipv4/conf/lo/arp_announce
       echo "0" >/proc/sys/net/ipv4/conf/all/arp_ignore
       echo "0" >/proc/sys/net/ipv4/conf/all/arp_announce
       echo "RealServer Stoped"
       ;;
*)
       echo "Usage: $0 {start|stop}"
       exit 1
esac
exit 0

[root@web-1 init.d]# chmod 755 realserver
[root@web-1 init.d]# service realserver start

6.安装lvs管理工具

[root@lvs-master ~]# yum install ipvsadm
[root@lvs-master ~]# ipvsadm -Ln
IP Virtual Server version 1.2.1 (size=4096)
Prot LocalAddress:Port Scheduler Flags
  -> RemoteAddress:Port           Forward Weight ActiveConn InActConn
TCP  172.16.0.100:80 rr persistent 50
  -> 172.16.0.113:80              Route   1      0          0         
  -> 172.16.0.114:80              Route   1      0          0 

7.测试
略

参考链接：
http://www.cnblogs.com/edisonchou/p/4281978.html