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[log in to unmask] wrote:
> Frank Bures wrote on 04/02/2009 02:24:50 PM:

>> When the duplicate mailing occurs, LISTSERV passes one (and just one) of
>> those blocks to sendmail again, some 10 minutes after the original
> mailing.
>> The block always contains external addresses.  They do not have to be
>> related to our central university mailing system.  Duplicate mailings
>> occurs intermittently to yahoo and other universities as well.  In other
>> words, any addresses that are in that single block of 100 entries will
> be
>> re-mailed.
>
> It sounds like the sendmail server is not confirming the receipt of the
> message with a 250 Message Accepted, so Listserv is not sure it went
> through and retries the message.

If that was true, why would it retry the message with only one of the 8
original blocks?  Why would those duplicate blocks always involve outside
addresses?  Would not be the retry recorded in listserv log?  If not, where
would it be logged?  The retry just appears in my maillog with the same
message ID but different sendmail ID with no errors or anything missing
preceding it.
All original mailings from sendmail to outside MTA's have "message accepted
for delivery".  There are no visible errors.

> Is the sendmail system under your
> control or someone else's?

It is my sendmail.

> Is that system heavily loaded?
>

Not really.  It runs on Quad Opteron machine with an average load of 2.

> Worst case, you might need a sniffer (or tcpdump) on the network
> connection
>

Wow, that would be a doozie :-(

Thanks
Frank

- --

Frank Bures, Dept. of Chemistry, University of Toronto, M5S 3H6
[log in to unmask]
http://www.chem.utoronto.ca

Please, reply to the above address only.  <lisfrank> does not accept replies.

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