On Thu, 2005-03-17 at 16:43 -0500, Guy wrote:
You have a very good point here. ISPs should limit the number of lookups to
9 or 8 so that a customer could use "include:ISP.com". Is this noted as a
SHOULD in the spec?
As a non-ISP, if I were to use 2 different ISPs, 1 from home and 1 on the
road, I would need to use 2 includes and maybe MX. In this case the ISPs
would need to be at 4 lookups each!
It seems like this does not scale well.
As a non-ISP, short of running your own SMTP server, you may want to
consider using SMTP AUTH (on the mail submission port, 587) to drop all
your mail off at your Email Service Provider's (which may be the same as
your ISP) system, no matter where you are. This should reduce SPF
record complexity considerably. If your ESP doesn't provide mail
submission via SMTP AUTH (or even POP before SMTP) service, you should
ask them to.
--
Andy Bakun <spf(_at_)leave-it-to-grace(_dot_)com>