Is Hotmail in the habit of ignoring MX records?

Jimmy Hess mysidia at
Sat Jul 28 01:00:30 UTC 2012

On 7/27/12, Tony Finch <dot at> wrote:
> That would be a seriously broken violation of the SMTP specification.
I would definitely agree it would be quite broken behavior,  but you
know,  I never said Hotmail's processing wasn't broken --  only that
they seem to honor MX records in the common case.    If you are doing
something unusual like    "mail MX    bla bla"

I would say you can't rule that out as a possible cause,  just because
some RFC suggests it should be OK.

The spec does say that you're not allowed to chain MX records.     But
i'm not so sure that the specification actually prohibits a SMTP
server from doing that, if someone
does try to chain MX records.

 it   may also be out of spec to have a  "MX"  record   point to a
dns  label  that a MX record exists for  in the first place.

> Tony.
> --
> f.anthony.n.finch  <dot at>

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