A response from the author of sendmail (Eric Allman):
Message-Id: <199403100626.WAA22201@mastodon.CS.Berkeley.EDU>
To: Adam Glass <glass@sun-lamp.cs.berkeley.edu>
From: Eric Allman <eric@CS.Berkeley.EDU>
cc: sendmail@vangogh.CS.Berkeley.EDU
Subject: Re: [sommerfeld@orchard.medford.ma.us: bin/165: sendmail could lose mail on hung nameserver.] 
In-reply-to: Mail from Adam Glass <glass@sun-lamp.cs.berkeley.edu> 
	dated Wed, 09 Mar 1994 21:57:34 PST
	<199403100557.VAA11113@sun-lamp.cs.berkeley.edu> 
Date: Wed, 09 Mar 1994 22:26:35 -0800

I don't believe this is correct -- or rather, it is only half correct.
It's true that the delay can be long if the nameserver is down, but
sendmail hasn't "accepted" the message until the 250 message at the
end of the DATA transaction (in SMTP) or it returns (in collect-from-
standard-input mode).  The problem is that it is trying to give you
an error message as soon as possible; this is in conflict with trying
to return as soon as possible.  There is no "right" answer.  I'll
consider trying to modify this for a future release, but for the time
being, I don't consider this a "bug" in the truest sense.

eric


Re:
: From:  Adam Glass <glass@sun-lamp.cs.berkeley.edu>
: Subject:  [sommerfeld@orchard.medford.ma.us: bin/165: sendmail could lose mai
l on hung nameserver.]
: Date:  Wed, 09 Mar 1994 21:57:34 -0800

: 
: this was filed against sendmail via us...haven't verified.
: 
: ------- Forwarded Message
: 
: Received: from localhost (mailman@localhost) by sun-lamp.cs.berkeley.edu (8.6
.5/8.6.5) id VAA11037 for netbsd-bugs-outgoing; Wed, 9 Mar 1994 21:50:05 -0800
: Received: from localhost (gnats@localhost) by sun-lamp.cs.berkeley.edu (8.6.5
/8.6.5) id VAA11018; Wed, 9 Mar 1994 21:50:03 -0800
: Date: Wed, 9 Mar 1994 21:50:03 -0800
: Message-Id: <199403100550.VAA11018@sun-lamp.cs.berkeley.edu>
: From: sommerfeld@orchard.medford.ma.us
: Reply-To: sommerfeld@orchard.medford.ma.us
: To: gnats-admin
: Cc: gnats-admin, netbsd-bugs
: Subject: bin/165: sendmail could lose mail on hung nameserver.
: In-Reply-To: Your message of Thu, 10 Mar 1994 00:33:31 -0500
: 	<199403100533.AAA00439@orchard.medford.ma.us>
: Sender: owner-netbsd-bugs@sun-lamp.cs.berkeley.edu
: Precedence: bulk
: 
: 
: >Number:         165
: >Category:       bin
: >Synopsis:       sendmail could lose mail on hung nameserver.
: >Confidential:   no
: >Severity:       serious
: >Priority:       medium

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