spf-discuss
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Re: CNAME limit

2005-07-21 18:38:48
On Thu, 21 Jul 2005, william(at)elan.net wrote:

Counting each CNAME as dns lookup is probably best. Then all other issues 
as far as limits and loops are already addressed by the spf draft.

I agree, but it has to be official.  Otherwise, people will get
different results depending on how they limit CNAME loops.
The current standard doesn't mention CNAME.  For that reason,
I think that the safest approach is to *not* count CNAME as "lookup",
but have an independent limit that is outside of the standard.

I will consider CNAME analogously to the limits on MX names and PTR
names, and apply a limit of 10 CNAMEs followed for each name lookup.

To be consistent, I would return TempErr on reaching it (since it
is not mentioned in the processing limits that return PermErr),
but I'll probably be ornery and return PermErr anyway, since the
domain has serious problems that need manual intervention to fix.

-- 
              Stuart D. Gathman <stuart(_at_)bmsi(_dot_)com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flamis acribus addictis" - background song for
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