🚀 go-pugleaf

Hello

Our machine (IBM RS 6000 AIX 3.1.5 3005) has been erratically bouncing
outgoing mail. An example of the kind of error it gives is:


From: MAILER-DAEMON (Mail Delivery Subsystem)
Subject: Returned mail: Service unavailable
Message-Id: <9203202251.AA30570@mail.physics.utah.edu>
To: pullin
Status: RO

  --- The transcript of the session follows ---
554 asterix.eng.buffalo.edu.tcp... 554 Service unavailable
554 arg-net@asterix.eng.buffalo.edu... Service unavailable



That is, it seems that for some reason it decides not to use the name
server and it tries to open a tcp/ip direct connection with the mail
destination. If the connection cannot be opened (network temporarily
unreachable, or if it is a foreign address with no direct connection)
it bounces the message. It should be noticed that usually re-sending
the message immediately does not cause any problem (the message goes
through OK). Sometimes maybe it has to be re-sent twice (it bounces
also the second time). The IBM people could only suggest "try
rebooting the machine" which did not help. I am using ELM 2.3 PL11 as
mailer and sendmail. I had a look at sendmail.cf and seems configured
OK. For instance it usually accepts without trouble "difficult"
foreign internet addresses, which proves it is using name servers to
send the message.  Again I remind that the problem is only sporadical
and is not reproducible, it happens about once a day to me, and I
usually send 20/30 outgoing messages a day.


Anyone can give me any hint? As you may infer from the wording of the
above text I am no expert in sendmail, tcp/ip or nameservers, so any
suggestion is welcome. Please reply by email, I can summarize if there
is interest. Thanks in advance.

Regards.
Jorge


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|Jorge Pullin, Department of Physics |  pullin@mail.physics.utah.edu        |
|201 JFB,  University of Utah        |  pullin@utahcca.bitnet               |
|Salt Lake City, UT 84112 USA        |  Tel:(801)581-5395 Fax:(801)581-4801 |
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