[comp.mail.sendmail] host name lookup failure

woods@ncar.ucar.edu (Greg Woods) (11/29/88)

   There are times when sendmail does not properly detect that a name server
failure is permanent rather than temporary. I am posting this before I go
looking through the source code in the hopes of avoiding re-invention of the
wheel.  An example occurs when one of our users suffers a temporary brain
seizure and mails to an address like "user@ics.ncar.edu" (our domain is
ucar.edu).  There is no such domain as ncar.edu, and when I pass ics.ncar.edu
through the name server via the "nslookup" command, it properly returns
"non-existent domain". However sendmail does not seem to recognize this as a
permanent failure, and the message is left in the queue. Then the user doesn't
find out about their typo until the maximum queue time (recently increased to 5
days) has elapsed. Has anyone else seen this problem?
  If it matters, I'm running a version of sendmail 5.58 hacked to work on
a Sun-4. If this is a known problem with 5.58 which has been fixed in 5.59,
then "upgrade to 5.59" is an acceptable answer, otherwise that answer avoids 
the issue. I'd like to upgrade but have not had the time. I'm also running BIND 
4.8 if that matters.

--Greg