Problem with consistent disconnection of IRC sessions

[Jeremy Chadwick]

On Thu, Apr 24, 2008 at 03:43:43PM -0400, Kevin K wrote:
> I am running a basic freebsd 7.0 pf router/firewall for my home computer. On
> this same machine I am usually running an IRC (tcp 6667) session.
> 
> It seems as though every 30 minutes to every several hours, my IRC session
> disconnects and reconnects itself.

There's a pretty good chance if it's a server on a popular network
(EFnet, DALnet, etc.), it may be under DoS, or may have incorrect
filtering rules applied to it.  If you're absolutely sure your rules are
OK, then it's probably not you.

The reason I say this:

IRC's protocol involves a PING check which the server sends to the
client every few minutes (usually; the server admin can set it to any
value he/she likes, but most people pick 5 minutes), and the client is
required to respond to that PING.  This is more or less a poor-man's TCP
keepalive.  This PING is not ICMP echo/echo-reply -- it's literally part
of the IRC protocol.

The regularity of people on public IRC networks pinging out/timing out
is immense.  I sit in #bsdports and see this happen to people hundreds
of times a day.

The issue may also be related to Internet peering, which you have
absolutely no control over.  Backbone providers break the Internet on a
nightly basis (this is not an exaggeration), and IRC is one of the most
"real-time" environments there is, so people notice.

-- 
| Jeremy Chadwick                                jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |