Thanks Valdis!
I added the 'FEATURE(nocanonify)' to my sendmail.mc and although I still
see the errors in my log file (which makes sense) it no longer prevents the
message from being delivered to the other recipients.

Gary Bannister
NetAccess Systems Inc.


On Wed, 19 Sep 2001 15:39:53 -0400, Valdis Kletnieks
<[log in to unmask]> wrote:

>On Tue, 18 Sep 2001 22:32:55 EDT, Gary Bannister <[log in to unmask]>  said:
>> We have recently upgraded to the above environment.  The problem is that
when sending out mail if Listserv comes across a subscriber's domain that
cannot be found (e.g., DNS servers are not reachable) then the error
messages below are produced and no messages are sent out.  There is a file
(e.g., 12345.mail) that sits in the spool directory indefinitely because of
the error.
>>
>> Has anyone come across this problem?  It appears that some configuration
change is need for Sendmail to let it ignore this error and continue
processing the list of addresses.
>>
>> -> RCPT TO:<[log in to unmask]>
>> 450 4.7.1 <[log in to unmask]>... Can not check MX records for
recipient host S
>> ITCOM.NET
>> 17 Sep 2001 01:35:27 >>> Error X'00C00E13' enqueuing mail for delivery
<<<
>> 17 Sep 2001 01:35:27  -> Severity: Error
>> 17 Sep 2001 01:35:27  -> Facility: SMTP error code
>> 17 Sep 2001 01:35:27  -> Abstract: Unspecified error (450) - See RFC821
et seq
>
>DNS for sitcom.net is provided by ns1.best.com, ns2.best.com, and
ns3.best.com,
>which however don't realize they are supposed to be providing DNS for it.
>The SOA for 'best.com' points you to [log in to unmask], who should be trying
to
>fix it.
>
>As far as a workaround goes, added 'FEATURE(nocanonify)' to your
sendmail.mc
>file, re-m4'ing a new .cf file, and restarting Sendmail should help you out
>a bit - this will bypass at least some of the DNS checks and maybe defer
>the 450 bounce until later (at actual delivery time).  It will also help
>speed up the initial submission considerably (I measured a 6X speedup in
>the handling of large lists when I originally did it many moons ago).
>
>
>--
>                                Valdis Kletnieks
>                                Operating Systems Analyst
>                                Virginia Tech