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Re: SUE.. what to do?



>
>        Often, on SMU's paticular server, I've noticed that if I write a
>message at 10 AM, it doesn't get posted until sometime around 4 PM in the
>same time zone.  Similarly, I've noticed that, like George and Tuck, I will
>see responses to messages before the message itself comes through!  Mickey,
>please enlighten us as to the nature of the server processes that make
>these delays possible!

The mail software on a lot of systems has two delivery modes, immediate
and background.  When mail arrives at the mail system (either from a
local user or another network connected computer) it generally tries to
immediately deliver the message to the recipient.  The recipient can
usually be a local user, a "forwarding" email address or a list of
either of these types.  Some systems also allow a copy of the message
to be submitted to a program for processing.  Most mailing lists use
this capability of a recipient being a list of other email addresses.
To deliver the message, the mail software has to make separate network
connections to each of the other computers and send them a separate
copy of the original email message.  The email headers are updated to
reflect this forwarding.  If, due to resource, network or other problems,
a message can't be delivered, it is saved in a queue for later delivery.
These deferred messages are batch processed at periodic intervals,
typically ranging from 15 min to a couple of hours.  If a message is
received by the list, and makes it to most users, but not you, it probably
will get delayed.  But if someone that got it responds, when that message
is processed by the list server, it may actually succeed in getting to
you before the batch processing delivers the original.  If there are
access problems between your computer and the list computer, these
reordering problems may happen.

Art Berggreen
art@acc.com