Have you looked at rinetd - man rinetd ;)
In your situation, the /etc/rinetd.conf file would look something like:
{gw-IP-addr} 21 192.168.50.20 21
{gw-IP-addr} 80 192.168.50.50 80
{gw-IP-addr} 4899 192.168.50.100 4899
....
logfile /var/log/rinetd.log
Also, you need to make sure these ports are open at the gateway i.e. not
blocked by a firewall and more importantly, are you happy to redirect web,
ftp, etc. requests to machines on your private network? For example, if the
internal web server is running IIS then you really need to be satisfied
that it is properly locked down before exposing it to external http
requests since if someone manages to compromise your internal web server
they can use it as a jumping off point to attack other machines on your
private network.
Anyway, just my two cents :)
Michael
"OKDesign oHG
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