If this is on our server, shouldn't it be rejecting all of the mail (from Mail.msu.edu) instead of just once in a while?
From: MSU Network Administrators Group [mailto:[log in to unmask]]On
Behalf Of Doug Nelson
Sent: Wednesday, December 22, 2004 2:29 PM
To: [log in to unmask]
Subject: Re: [MSUNAG] Mail question
Javier Ornelas writes:
> Periodically, I receive calls from our users (on our Exchange Server)
> who say that Mail.msu.edu users are trying to e-mail them, but are
> receiving errors such as:
> This message was created automatically by mail delivery software.
> A message that you sent could not be delivered to one or more of its
> recipients. This is a permanent error. The following address(es) failed:
> [log in to unmask]
> SMTP error from remote mailer after initial connection:
> host ht.msu.edu [220.127.116.11]: 554 <sys09.mail.msu.edu[18.104.22.168]>:
> Client host rejected: too many connections
> Can someone help shed some light on what is causing these errors? Is
> there something I need to change on our Exchange Server? As I said, it
> is only periodically. Most of the time, there is no problem.
If I'm reading this correctly, the mail server for ht.msu.edu is rejecting
the incoming mail with a permanent error (code 554; 5xx codes indicate
permanent errors) for what should be a transient condition. Your mail
server should be returning a 4xx (temporary error) code, rather than a
5xx code. That would cause the sending mail system to retry the message,
and (hopefully) eventually get through.
Doug Nelson, Network Manager | [log in to unmask]
Academic Computing and Network Services | Ph: (517) 353-2980
Michigan State University | http://www.msu.edu/~nelson/