將本地接口IP 61.144.14.72 的3389端口 轉發到 116.6.73.229的3389
（主要訪問到61.144.14.72的3389端口，就會跳轉到116.6.73.229的3389）
【步驟】
1、 首先應該做的是/etc/sysctl.conf配置文件的 net.ipv4.ip_forward = 1 默認是0 這樣允許iptalbes FORWARD。
2、 service
iptables stop 關閉防火牆
3、 重新配置規則
iptables -t nat -A PREROUTING --dst 61.144.14.72 -p tcp --dport 3389 -j DNAT --to-destination 116.6.73.229:3389
iptables -t nat -A POSTROUTING --dst 116.6.73.229 -p tcp --dport 3389 -j SNAT --to-source 61.144.14.72
service iptables save
將當前規則保存到 /etc/sysconfig/iptables
若你對這個文件很熟悉直接修改這裡的內容也等於命令行方式輸入規則。
5、 啟動iptables 服務, service iptables start
可以寫進腳本，設備啟動自動運行；
# vi /etc/rc.local
#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.
touch /var/lock/subsys/local
sh /root/myshipin.log
---------------------------------------------------------------------
vi myshipin.log
#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.
iptables -F -t nat iptables -t nat -A PREROUTING --dst 61.144.14.72 -p tcp --dport 3389 -j DNAT --to-destination 116.6.73.229:3389
iptables -t nat -A POSTROUTING --dst 116.6.73.229 -p tcp --dport 3389 -j SNAT --to-source 61.144.14.72
~
----------------------------------------------------------------
TCP
iptables -t nat -A PREROUTING --dst 61.144.14.87 -p tcp --dport 9304 -j DNAT --to-destination 10.94.143.204:9304
iptables -t nat -A POSTROUTING --dst 10.94.143.204 -p tcp --dport 9304 -j SNAT --to-source 61.144.14.87
UDP
iptables -t nat -A PREROUTING --dst 61.144.14.87 -p udp --dport 9305 -j DNAT --to-destination 10.94.143.204:9305
iptables -t nat -A POSTROUTING --dst 10.94.143.204 -p udp --dport 9305 -j SNAT --to-source 61.144.14.87
