Martijn de Munnik:
> On Wed, 20 Jan 2010 07:20:01 -0500 (EST), wie...@porcupine.org (Wietse
> Venema) wrote:
> > Martijn de Munnik:
> >> Hi list,
> >>
> >> I have a problem with delivering mail to a host and get this error:
> >>
> >> host mx2.amsterdam.nl[145.222.14.10] said: 421 enepmx02.amsterdam.nl
> >> Error: timeout exceeded (in reply to end of DATA command)
> >>
> >> This error only seems to occur with 'large' mails. Currently I have a
> >> mail
> >> of ~600KB and ~8MB stuck in the queue. I don't think this is a postfix
> >> issue on our site but an issue with the mailserver on the other site.
> >> What
> >> can cause such issues?
> >
> > Record a tcpdump trace. The way the session fails will indicate
> > the kind of problem (MTU, Window scaling, and so on).
> >
> > http://www.postfix.org/DEBUG_README.html
> >
> > Wietse
>
> Ok, I tried that and I'm not really sure where to look for. I opened the
> tcpdump file in wireshark and there are a lot of warnings and notes in the
> file.
>
> --
> Notes:
> Duplicate ACK(#1) [145.222.14.10 -> 213.207.90.2]
> Duplicate ACK(#2) [145.222.14.10 -> 213.207.90.2]
> Duplicate ACK(#3) [145.222.14.10 -> 213.207.90.2]
> Duplicate ACK(#4) [145.222.14.10 -> 213.207.90.2]
> .
> .
> .
> Duplicate ACK(#44) [145.222.14.10 -> 213.207.90.2]
> Retransmission (suspected) [213.207.90.2 -> 145.222.14.10]
>
> Warnings:
> Fast retransmission (suspected) [213.207.90.2 -> 145.222.14.10]
> Out-Of-Order segment [213.207.90.2 -> 145.222.14.10]
> --
>
> This is abracadabra for me ;)
If you can make the "tcpdump -nr /file/name" output available then
people who understand TCP/IP can look at it.
Wietse
