项目背景

利用lvs的vs/NAT技术实现一个由负载调度器和两个web服务器组成的架构！

试验环境

vmware workstation 11

centos6.5的系统下

load balance：ip：192.168.0.32   vip：192.168.1.32   关闭iptables  setenforce0

user：ip：192.168.1.39   关闭iptables  setenforce0

real_server01:192.168.0.10  gw:192.168.0.32 关闭iptables  setenforce0

real_server02:192.168.0.36  gw:192.168.0.36 关闭iptables  setenforce0

SecureCRT （ssh远程连接软件）

架构图：

实验过程：

一、在load balance上面安装ipvsadm

直接用yum安装

因为我已经安装成功了，所以显示已安装！

二、在load balance上面执行脚本

[root@Load_Balancer ~]# cat lvs.sh

#!/bin/sh

#set ip_forward ON for vs-nat director (1 on, 0 off).

cat /proc/sys/net/ipv4/ip_forward

echo "1" >/proc/sys/net/ipv4/ip_forward

#director is gw for realservers

#turn OFF icmp redirects (1 on, 0 off)

echo "0" >/proc/sys/net/ipv4/conf/all/send_redirects

cat /proc/sys/net/ipv4/conf/all/send_redirects

echo "0" >/proc/sys/net/ipv4/conf/default/send_redirects

cat /proc/sys/net/ipv4/conf/default/send_redirects

echo "0" >/proc/sys/net/ipv4/conf/eth0/send_redirects

cat /proc/sys/net/ipv4/conf/eth0/send_redirects

#clear ipvsadm tables

/sbin/ipvsadm -C

#install LVS services with ipvsadm

#add telnet to VIP with rr sheduling

/sbin/ipvsadm -A -t 192.168.1.32:80 -s rr

#first realserver

/sbin/ipvsadm -a -t 192.168.1.32:80 -r 192.168.0.10:80 -m -w 1

#second realserver

#forward telnet to realserver 192.168.0.36 using LVS-NAT (-m), with weight=1

/sbin/ipvsadm -a -t 192.168.1.32:80 -r 192.168.0.36:80 -m -w 1

#list ipvsadm table

/sbin/ipvsadm

三、在real server01上面执行脚本

[root@real_server01 ~]# cat real_server01.sh

#!/bin/sh

#show routing table

/bin/netstat -rn

#set_realserver_ip_forwarding to OFF (1 on, 0 off).

echo "0" >/proc/sys/net/ipv4/ip_forward

cat /proc/sys/net/ipv4/ip_forward

四、在real server02上执行脚本

[root@real_server02 ~]# cat real_server02.sh

#!/bin/sh

#show routing table

/bin/netstat -rn

#set_realserver_ip_forwarding to OFF (1 on, 0 off).

echo "0" >/proc/sys/net/ipv4/ip_forward

cat /proc/sys/net/ipv4/ip_forward

五、测试，在user上打开浏览器输入vip 192.168.1.32

可以看到，我在user服务器上访问load balance上面的vip，可以访问到后端的web集群。

总结：VS/NAT技术是我们呢常用的构建lvs集群的技术，当然你可以在后端部署十几台或者几十台服务器。希望大家都有所得