Thanks for the clarification, but can someone else verify my findings
about swbell.net?   I'm not "totally" sure that I have isolated the
problem to their systems.....


Thanks

Jason



-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]] On Behalf Of Len Conrad
Sent: Thursday, September 12, 2002 7:57 PM
To: [EMAIL PROTECTED]
Subject: RE: [IMail Forum] Swbell.net mail system Screwed??????



>Its not "round robin", the RFC is quite explicit about this:
>    Multiple MX records contain a preference indication that MUST be
used
>    in sorting (see below).  Lower numbers are more preferred than
higher
>    ones.  If there are multiple destinations with the same preference
>    and there is no clear reason to favor one (e.g., by recognition of
an
>    easily-reached address), then the sender-SMTP MUST randomize them
to
>    spread the load across multiple mail exchangers for a specific
>    organization.

The mosts MTA's, still, will use the physical order of the MX records as

they arrive in the DNS answer packet, take the first MX hostname, and
then 
take the first physical A record for that hostname.

It's the DNS (BIND at least) that varies the order on the physical
record 
sequence. By default, BIND is ordering is "cyclic".

Len


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