Hello to all
Im new to linux. One of my voice application running on a windows 2003 server and that specific application need 172.27.0.1 ip to run.So i set windows 2003 server ip to 172.27.0.1(private ip).now i want to access my windows server's voice application from internet. For this reason i want to setup a linux server which ip is 203.91.148.10(real ip).Now i want to access windows server's voice service from internet though this linux server. So can u people help me to redirect or forward all packets(tcp,udp,icmp) to windows server to get the service from that application running on windows server when user hits linux server's real ip from internet.
internet_user->linux_server->windows_server(voice application
)

Do you know what ports and protocols the voice application uses? You will need them.

The best way I know how to do it, is to use an iptables rule like..

..just modify the port numbers and protocols that your application requires.

If you're new to Linux, I'd recommend taking a look at the IP-Masquerade-HOWTO.
and doing a bit of reading on iptables. They'll help you set up a decent firewall.

Hope this helps.

Hello,
Thanks for your reply. I like to know is that possible to redirect all ports packets to 172.27.0.1 from 203.91.100.4(real ip)
Thanks in advanced

i dont understand, did you ask again if its possible? If so. Yes it and camh gave two nice simple rules to help you achieve your goal but again like he say you'll need to know the protocol tcp/udp/etc and which ports they need. Note for defining more than one port in sequence use a ":"

example

iptables -t nat -A PREOUTING -p tcp -i eth0 --dport 560:562 -j DNAT --to-destination 192.168.1.2

this will forward ports 560, 561, and 562 to 192.168.1.2

hope it helps