This brief document corrects an error in RFC 5451 regarding
one Email Authentication Result Name (see RFC Editor Erratum
#2617). Namely, the name "hardfail" is incorrect, and the name
"fail" is correct (and is used in all existing implementations).
As far as can be determined, all implementations of Sender
Policy Framework (SPF) use "fail" instead of "hardfail", as
specified in Section 2.5.4 of RFC 4408. The same is true of
Sender-ID (see Section 5.3 of RFC 4406). The error in RFC
5451 was not caught during review of that specification.
Although in practice the error has not yet caused confusion
among implementers, it is best to correct the error in order to
forestall possible interoperability problems.
Working Group Summary
This document is not the product of a working group.
Existing implementations use "fail" (RFC 4406, RFC 4408)
instead of "hardfail" (RFC 5451), so there are implementations
of the correction described in this specification. This document
simply corrects the error in RFC 5451 and does define any new
This correction was discussed on the firstname.lastname@example.org
and email@example.com lists. Some people thought it might be
appropriate to correct the error if and when the SPFBIS WG,
whereas others thought it would be better to correct this simple
error without opening up discussion of RFC 5451 more generally
(and thus possibly delaying the fix). There was agreement that
correcting error sooner rather than later would be preferable.
The Document Shepherd / Responsible Area Director is