RedHat下隧道模式的负载均衡
首先：隧道模式的负载均衡的工作原理：客户机访问director机，director机将客户端的请求发送到真实服务器，然后真实服务器将请求应回应的结果直接回应给客户机。真实服务器间可以是不通网段--即各服务器之间可以夸网。 这种方式不仅减轻director机的压力，效率高，还能在空间上得到运用。但在中国似乎暂时行不通(因为很少有企业用过...)。一般适用于大中型企业。
实验环境： 两台主机服务器：192.168.0.11 和 192.168.0.12
中转机： 192.168.0.13 和 192.168.0.19
客户机：192.168.0.10
(主机名要跟IP保存一致。iptables要清空--iptables -F 。selinux 关闭)
实验步骤：
A.服务器：
1。192.168.0.11
# yum install -y httpd
# service httpd start
# echo "192.168.0.11" >/var/www/html/index.html
# route add default gw 192.168.0.13
# vim /etc/init.d/shutarp
-------------------------------
#!/bin/sh
VIP=192.168.0.19
. /etc/rc.d/init.d/functions
case "$1" in
start)
echo "Tunl port starting"
ifconfig tunl0 $VIP netmask 255.255.255.255 broadcast $VIP up
/sbin/route add -host $VIP dev tunl0
echo "1" >/proc/sys/net/ipv4/conf/tunl0/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/tunl0/arp_announce
echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
sysctl -p
;;
stop)
echo "Tunl port closing"
ifconfig tunl0 down
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 0 > /proc/sys/net/ipv4/conf/all/arp_announce
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esac
-------------------------------
# service shutarp start
2。192.168.0.12
# yum install -y httpd
# service httpd start
# echo "192.168.0.12" >/var/www/html/index.html
# route add default gw 192.168.0.13
# vim /etc/init.d/shutarp
-------------------------------
#!/bin/sh
VIP=192.168.0.19
. /etc/rc.d/init.d/functions
case "$1" in
start)
echo "Tunl port starting"
ifconfig tunl0 $VIP netmask 255.255.255.255 broadcast $VIP up
/sbin/route add -host $VIP dev tunl0
echo "1" >/proc/sys/net/ipv4/conf/tunl0/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/tunl0/arp_announce
echo "1" >/proc/sys/net/ipv4/conf/all/arp_ignore
echo "2" >/proc/sys/net/ipv4/conf/all/arp_announce
sysctl -p
;;
stop)
echo "Tunl port closing"
ifconfig tunl0 down
echo 1 > /proc/sys/net/ipv4/ip_forward
echo 0 > /proc/sys/net/ipv4/conf/all/arp_announce
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esac
-------------------------------
# service shutarp start
B.中转机：
1。安装 ipvs服务：
# yum clean all
# yum install -y ipvsadm
2。打开ip转发功能，关闭其他服务，设置中转
# vim /etc/init.d/lvsDR
---------------------------------
#!/bin/sh
VIP=192.168.0.19
RIP1=192.168.0.11
RIP2=192.168.0.12
GW=192.168.0.1
. /etc/rc.d/init.d/functions
case "$1" in
start)
echo " start LVS of DirectorServer"
/sbin/ifconfig tunl0 $VIP broadcast $VIP netmask 255.255.255.255 up
/sbin/route add -host $VIP dev tunl0
/sbin/ipvsadm -C
/sbin/ipvsadm -A -t $VIP:80 -s rr
/sbin/ipvsadm -a -t $VIP:80 -r $RIP1:80 -i
/sbin/ipvsadm -a -t $VIP:80 -r $RIP2:80 -i
/sbin/ipvsadm
;;
stop)
echo "close LVS Directorserver"
ifconfig tunl0 down
/sbin/ipvsadm -C
;;
*)
echo "Usage: $0 {start|stop}"
exit 1
esac
---------------------------------
# service lvsDR start (执行脚本)
# vim /bin/shutarp
-------------------------------
#!/bin/bash
VIP=192.168.0.19
/sbin/ifconfig lo:0 $VIP broadcast $VIP netmask 255.255.255.255 up
/sbin/route add -host $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
-------------------------------
# shutarp
C。客户端：
在浏览器中打开： http://192.168.0.19/ (重复刷新，看显示的页面：如果是不同页面说明实验成功！)