Internal port forwarding

[getUP]

Uhu, yet another question about port forwarding.
However, I only want to forward internal TCP packages.

An example situation of where we want to use this is:

server1:
ip: 10.0.0.200
ssh port: 22

server2:
ip: 10.0.0.220
ssh port: 10201

server3:
ip: 10.0.0.230
ssh port: 10212

Now, when a request is made from server1 to server2, we do not want to specify a port, so just 'ssh user@10.0.0.220' should be sufficient. The same for 'ssh user@10.0.0.230'.

Therefor, TCP traffic to 10.0.0.200 on port 22 should not be directed as that would make the box inaccessable. Only traffic from server1 to other servers - and only when specified.

My iptables is lacking a lot - but the manual pages aren't giving any help either. From how it looks, iptables is not capable of just doing that, is it? If so, what other tools should I be looking for?

Thanks!

[framp]

There's an easier way to get it done. Create a ~/.ssh/config file and insert statements

host 10.0.0.220
port 10201
host 10.0.0.230
port 10212

Details see man ssh_config.

[getUP]

There's an easier way to get it done. Create a ~/.ssh/config file and insert statements

host 10.0.0.220
port 10201
host 10.0.0.230
port 10212

Details see man ssh_config.

Maybe I gave the wrong example by using SSH, it's mainly intended for Exim. Maybe it's possible to accomplish that by configuration as well, but I'm not so sure it can.