DIP:192.168.199.230
VIP:192.168.199.235
RIP:192.168.199.231(232)
负载均衡器：
[root@LVS001 ~]# sysctl -w net.ipv4.ip_forward=0
net.ipv4.ip_forward = 0
[root@LVS001 ~]# ifconfig eth1:1 192.168.199.235 netmask 255.255.255.0 up
[root@LVS001 ~]# ipvsadm -A -t 192.168.199.235:80 -s wrr -p 20
[root@LVS001 ~]# ipvsadm -a -t 192.168.199.235:80 -r 192.168.199.232:80 -i -w 1
[root@LVS001 ~]# ipvsadm -a -t 192.168.199.235:80 -r 192.168.199.231:80 -i -w 1
Real-Server：
[root@RealServer001 ~]# /sbin/modprobe ipip
[root@RealServer001 ~]# modinfo tun #确认内核是否有tun模块
filename: /lib/modules/2.6.32-358.el6.x86_64/kernel/drivers/net/tun.ko
alias: char-major-10-200
license: GPL
author: (C) 1999-2004 Max Krasnyansky <maxk@qualcomm.com>
description: Universal TUN/TAP device driver
srcversion: B81D2A0EFFDD495B07C94AB
depends:
vermagic: 2.6.32-358.el6.x86_64 SMP mod_unload modversions
[root@RealServer001 ~]# modprobe tun #加载内核模块
[root@RealServer001 ~]# lsmod | grep tun
tun 17031 0
tunnel4 2943 1 ipip
[root@RealServer001 ~]# ifconfig tunl0 192.168.199.235 netmask 255.255.255.255 broadcast 192.168.199.235
[root@RealServer001 ~]# ifconfig tunl0 up
[root@RealServer001 ~]# route add -host 192.168.199.235 dev tunl0
[root@RealServer001 ~]# echo "2" >/proc/sys/net/ipv4/conf/tunl0/arp_announce
[root@RealServer001 ~]# echo "1" >/proc/sys/net/ipv4/conf/tunl0/arp_ignore
[root@RealServer001 ~]# echo "0" >/proc/sys/net/ipv4/conf/tunl0/rp_filter
[root@RealServer001 ~]# echo "1" >/proc/sys/net/ipv4/conf/tunl0/forwarding
[root@RealServer001 ~]# echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
[root@RealServer001 ~]# echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
可能错误：
[root@RealServer001 ~]# ifconfig tun10 192.168.199.235 broadcast 192.168.199.235 netmask 255.255.255.255 up
SIOCSIFADDR: No such device
tun10: unknown interface: No such device
SIOCSIFBRDADDR: No such device
tun10: unknown interface: No such device
SIOCSIFNETMASK: No such device
tun10: unknown interface: No such device