I have 2 networks 10.10.10.0/24 and 10.10.11.0/24 that I want to connect with a slackware based FW/router. My router/fw has the 10.1 and 11.1 addresses for the respective networks.

If I try to ssh from any of the network to the other the traffic never gets there. For example if I ssh from 10.4 to 11.6, 11.6 never receives the traffic. The strange thing is that if I try to ssh from 10.4 to 11.1 I get connected just fine (it’s like the traffic is never being routed out the interfaces.)

There are no IPTables rules (actually IPT are not even being started). Any ideas on what I may try to get this to work will be appreciated.

You'd need to enable IP Forwarding on your Slackware router box:

This can be done with the following command.

echo 1 > /proc/sys/net/ipv4/ip_forward

and similarly, disabled by the following command:

echo 0 > /proc/sys/net/ipv4/ip_forward

when the box is restarted the enable command would need to be re-executed, so it may be an idea to put it in a script which is executed when the machine starts. rc.local for example.

Hope this helps. Good luck

To enable IP Forwarding at boot just chmod 755 /etc/rc.d/rc.ip_forward

Also is there a seperate NIC for each network? Are you using DHCP?