Question : ssh port forwarding issue

This is driving me up the wall.

setup:
office has zoom adsl 1port  ethernet router, connected to a smoothwall firewall, via DMZ used for configuration of router, and testing various bits n peices..

internal network is mix of win2k,xp, redhat 7.3 (old server) and suse 9.2

Software company occasionally has to SSH into RH server.

Using PuTTY, they Connect to port 22 on the router, which is forwarded to 122 on a smoothwall express box (recently replaced a clarkconnect box), in turn is forwarded to 22 on the RH box.

This worked fine until this week. now puTTY just hangs, without receiving the key.

poked around a bit.

Can connect from DMZ to suse servers through smoothwall (SSH and VNC).
Can`t connect from DMZ to RH server through smoothwall
Can only connect to RH server from local subnet, on any of it's 3 ethernet ports (SSH and VNC).
Tried connecting 3rd ethernet port on RH box direct to router. no go

externally, shieldsup! shows open ports as stealthed.
nmap shows the ports as open, but needs -P0 to work.

Additionally, cannot connect from outside router IP to inside network via smoothwall.

a tracert from a dial up account took 12 hops at about 100msec each, whereas a ping took 46msec

Answer : ssh port forwarding issue

Sounds like the RedHat server has lost it's default gateway setting....that would be where I would look.