Francisco Neira wrote:
Actually I am using the most recent versions of everything in the Centos
repositories.
You can use
http://postfix.wl0.org/
The same messages that are accepted in gmail, hotmail and my office's
exim are rejected or at least not completed in that domain.
My logic tells me that the problem is caused by the receiving MTA but I
need to demonstrate that with evidence to a cocky stubborn M$ postmaster.
it may be that the server disconnects because of message size limits.
http://service1.symantec.com/support/ent-gate.nsf/docid/2007090713043654
or it may be a network problem. for example, aggressive ICMP filtering
will break PMTU discovery (ICMP type 3 Code 4 is needed for PMTU discovery):
$ ping mail.osterlingfirm.com
PING mail.osterlingfirm.com (200.31.124.213): 56 data bytes
^C
--- mail.osterlingfirm.com ping statistics ---
19 packets transmitted, 0 packets received, 100.0% packet loss
so it looks like they love icmp filtering... sigh.
another candidate is TCP windows scaling, which is mishandled by old
firewalls.
http://www.google.fr/search?q=firewall+bug+tcp+windows+scaling
If this is the case, transfers from a "recent" system (linux, bsd, ...
windows vista) may fail.
Nevertheless, I generate the file with tcpdump and tomorrow morning I'll
try to interpret it with wireshark.
Thanks for the ideas and excuse me for that first HTML posting.
