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I set up a Fedora Core 2 machine to act as a gateway/router so that I could do NAT and split-route VPN traffic to my office and everything else directly out to the 'net, without having to do anything special on my other computer(s) (I primarily use a PowerBook behind the router).
Everything has worked fine for some time. A few months ago, I set up inbound port mapping to support BitTorrent from a single machine behind the router. It's been working like gangbusters.
A couple of weeks ago, the power supply started giving me problems, so I replaced it (meaning I had to reboot my gateway). Around the same time (I can't say for sure), I lost the ability to connect to port 6969 on external hosts. 6969 is used by the BitTorrent protocol to establish the connection to the other peers (it's the "tracker" server).
I have experimented by using telnet to see what I could and could not connect to, and from where. Here's the scoop: I can connect to port 80 on any host out there from any host, including the router and my PowerBook. I can connect to port 6969 from the router, but NOT from the PowerBook (when I do, it times out):
Aero:~ rmann$ telnet oasis.bscn.com 80 Trying 216.60.208.252... Connected to oasis.bscn.com. Escape character is '^]'.
Connection closed by foreign host. Aero:~ rmann$ telnet oasis.bscn.com 6969 Trying 216.60.208.252... telnet: connect to address 216.60.208.252: Operation timed out telnet: Unable to connect to remote host
So, I'm fairly certain that there's something in the iptables rules that's blocking this one port, but I sure can't find it. The only port-specific rules I can see (using iptables -L on all tables) are for mapping the inbound ports 6881-6999...hmm. I changed this to exclude 6969, and I can connect now.
Any ideas why that would be the case?
TIA
-- Rick
