外网 内网
——–>[nodes]——> （nodes上的部分服务仅仅绑定了内网端口）

1. 采用Iptables方式
   对于监听在127.0.0.1的未必能行，待商榷
   [source language=”shell”]
   # echo 1 > /proc/sys/net/ipv4/ip_forward
   # iptables -t nat -A PREROUTING -p tcp -d 外网ip –dport 80 -j DNAT –to-destination :8080
   # iptables -t nat -A POSTROUTING -p tcp -s 内网ip –sport 8080 -j SNAT –to-source :80

   [/source]

2. ssh端口转发模式
   http://my.oschina.net/guol/blog/115235
3. netcat(http://linux.die.net/man/1/nc)

   [source language=”shell”]
   # yum install nmap-ncat
   # nc -l 29000|nc 10.47.107.248 27000
   [/source]

4. socat (http://www.dest-unreach.org/socat/doc/socat.html#EXAMPLES)

[source language=”shell”]
#wget http://www.dest-unreach.org/socat/download/socat-1.7.3.0.tar.gz
# tar xzvf socat-1.7.3.0.tar.gz
# cd socat-1.7.3.0 && ./configure && make && make install
#socat TCP4-LISTEN:www TCP4:www.domain.org:www
[/source]

PortForwarding: https://en.wikipedia.org/wiki/Port_forwarding
http://www.cyberciti.biz/faq/linux-port-redirection-with-iptables/
https://help.ubuntu.com/community/SSH/OpenSSH/PortForwarding

iptables实现端口映射