Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!aplcen!jhunix!andy
From: andy@jhunix.HCF.JHU.EDU (Andy S Poling)
Newsgroups: comp.mail.sendmail
Subject: Re: Deferred mail on Sendmail.5.61
Summary: MX RRs
Keywords: deferred, MXs, DNS
Message-ID: <4458@jhunix.HCF.JHU.EDU>
Date: 11 Mar 90 21:15:27 GMT
References: <1894@qualcom.qualcomm.com>
Reply-To: andy@jhunix.UUCP (Andy S Poling)
Followup-To: comp.mail.sendmail
Organization: The Johns Hopkins University - HCF
Lines: 39

In article <1894@qualcom.qualcomm.com> edmund@qualcom.qualcomm.com (The Silver Surfer) writes:
>I seem to be having problems having sendmail.5.61 deferring mail, when
>mail is sent to a local host that is down. The sendmail that I am using
>now (sendmail.4.0), doesn't seem to have this problem.
[...]
>This is what it looks like, sending mail to cancun (who's down) using
>sendmail.4.0 in verbose mode:
>
>edmund@cancun... Connecting to cancun.qualcomm.com via ETHERNET...
>Trying 129.46.4.6... Connection timed out during user open with cancun.qualcomm.com
>edmund@cancun... Deferred: Host cancun.qualcomm.com is down
[...]
>This is what senmdail.5.61 looks like in verbose mode with the same .cf file:
>
>edmund@cancun... Connecting to cancun.qualcomm.com (tcpld)...
>220 qualcom.qualcomm.com Sendmail 5.61-bcr/1.34 ready at Tue, 6 Mar 90 10:01:12 -0800
>>>> HELO qualcom.qualcomm.com
>553 Local configuration error, hostname not recognized as local

This looks like you're running into MX problems.  Sendmial 5.61 doesn't
(IMHO) handle very well the situation where it is the "secondary" MX for a
host that is down.  It will connect to itself and cause the "configuration
error".  The mail in question then gets bounced back with this very
un-helpful error message.

I think that if all MXs of lower preference are un-reachable, sendmail
should re-queue the mail and retry on the next queue run.  I began to
implement this behavior, but never finished the job.

You don't have this problem with sendmail 4.* because it doesn't
use MXs.

-Andy

--
Andy Poling                              Internet: andy@gollum.hcf.jhu.edu
Network Services Group                   Bitnet: ANDY@JHUVMS
Homewood Academic Computing              Voice: (301)338-8096    
Johns Hopkins University                 UUCP: mimsy!aplcen!jhunix!gollum!andy