gmail.com problems and this list

[Wolfgang S. Rupprecht]

Harald Welte <laforge at openmoko.org> writes:
> yes, I can confirm this.  This is from our exim4 installation on the
> list server:
> 2007-07-07 09:17:19 1I74UH-0005cE-SD <= robin.paulson at gmail.com H=py-out-1112.google.com [64.233.166.176] P=esmtp S=3940 id=2f3aa2770707070010k7407439axfaa269de33395ea2-JsoAwUIsXosN+BqQ9rBEUg at public.gmane.org
> 2007-07-07 09:27:18 1I74dw-000682-6l <= robin.paulson at gmail.com H=py-out-1112.google.com [64.233.166.181] P=esmtp S=3940 id=2f3aa2770707070010k7407439axfaa269de33395ea2-JsoAwUIsXosN+BqQ9rBEUg at public.gmane.org
>...

This isn't enough to tell which side is causing the misbehavior.  I
find that slapping a tcpdump(1) on the interface and logging to a file
is the simplest way to see what is really happening (eg. tcpdump -w
/xxx/logfile -s 1500 -i eth0).  Running wireshark() (formerly
ethereal()) and using the "follow tcp stream" shows the back and forth
conversation.  In this case I bet you'll see that gmail is either
timing out due to slow replies or packets are getting dropped and
gmail is asking for lots of retransmissions and eventually throws in
the towel.

My gut feel is that the receiver is most likely the villain with
either and overloaded CPU and/or lots of slow antispam filters that
need to be run.

(If you want help setting up the tcpdump or looking at the logs, feel
free to send mail to my gmail address.  I've tracked down enough mail
problems like this that this is very old hat.)

-wolfgang
-- 
Wolfgang S. Rupprecht                http://www.wsrcc.com/wolfgang/
IPv6 on Fedora 7 http://www.wsrcc.com/wolfgang/fedora/ipv6-tunnel.html