ietf-smtp
[Top] [All Lists]

Re: [ietf-smtp] SPF DNS query limits

2016-05-25 07:05:36
'include:%{i4r}.spf.ebay.com'. T
Yuck.  That feels really fragile.
Why?

Is it just that SPF macros aren't well implemented (despite them being a key part of SPF), or something else?

Partly it's poor SPF implementations, partly that it's a much more complex set of records to publish. Your example as written requires a record for every outbound IPv4 mail server, and probably still puts all of the IPv6 servers into one record or for a really large provider one record per RIR from whom they get space. Neither strike me as something that's likely to be maintained reliably.

Regards,
John Levine, johnl(_at_)taugh(_dot_)com, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail.

_______________________________________________
ietf-smtp mailing list
ietf-smtp(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/ietf-smtp