[lug] tcp keepalive

[Michael Deck]

I'm having a problem with network session timeouts that you all might be
able to help with. This began because I noticed that I was getting
disconnected from Netmeeting sessions after about half an hour of
inactivity. Since I'm using Linux as a router for an otherwise Win95
network, the fine folks at M$ tech support started to point at the router
as the problem. I pooh-poohed this but then I tried going to the internet
via dialout ISP (rather than Linux-routed ISDN) and Eheu! no disconnect. I
was still skeptical but then I noticed another problem. I'm running an
application that accesses a Postgres database across the Internet. It makes
a connection then does a lot of computation then wants to re-access the
connection. After about half an hour (!) if there's no database activity,
it can't re-establish the connection. So now I'm thinking, maybe there's
something to what M$ said. They maid noises about tcp keepalives being sent
(or not). 

After a frustrating hour of searching usenet and the man pages (but not
knowing really what I'm searching for) I came away with the impression that
there is something I need to do to make my system always send keepalives
over any TCP/IP connection, but I don't exactly know what it is. I'm
hesitant to just start fiddling. It's also possible that my firewall is
holding up the packets tho I think it's permitting almost all *outbound*
traffic. 

Can someone point me to the right man page or docs, or provide a little
guidance about how to fix this? I'm running stock RH5.1 (kernel 2.0.36). 

TIA,
  Mike

Michael Deck
Cleanroom Software Engineering, Inc.