Sendmail and Unexpected EOM

[Quentin Campbell]

>-----Original Message-----
>From: mailscanner-bounces at lists.mailscanner.info [mailto:mailscanner-
>bounces at lists.mailscanner.info] On Behalf Of Scott Silva
>Sent: 29 October 2007 17:55
>To: mailscanner at lists.mailscanner.info
>Subject: Sendmail and Unexpected EOM
>
>I'm getting a lot of collect: premature EOM: unexpected close
>errors from certain servers, and a google gives me much conflicting
>info.
>
>Running CentOS 4 and current stable MailScanner.
>
>  I have tried decreasing the MTU on the external interface, and only
>succeeded in stopping all traffic. Tried disabling window scaling, and
>that also had no effect. Could the default be to set no-fragment on
packets
>from CentOS 4?
>[snip]

Scott

What evidence do you have that it is your end rather than the sending
site, or somewhere in between, that is at fault?

Although a 'traceroute' does not always work (because ICMP is disabled
at gateways) it may indicate some large delay on the route between the
sender and you.

I also see the 'premature EOM' messages here and have assumed them to be
a problem for the sender, not us. 

Where they occur after we have returned 'REJECT' status for all
recipients after a DNSBL lookup, I assume that because the sender is a
spammer they do not bother to close down the SMTP connection with a
RESET or QUIT and simply move on to start a new SMTP connection with
another target.

Quentin