I was looking at how various sites have their SPF records set, and found a site whose SPF record ends with +all
.
This seems to be a bad idea, and spf-all says the following about the matter:
+all Pass The email is never a forgery. This option should not be used.
Yet I cannot find anything in the RFC that says this is banned, so it appears to be a valid record.
Is this a valid record? And if so, would most spam filters treat this as an indication to raise the required level of spammyness of a message from this domain before it is treated as spam, or would it simply ignore the record, or count it against the domain?
Best Answer
SPF is defined in RFC 7208.
The "all" keywork is defined as such:
You even have this example:
or
So
+all
is useful, and certainly not banned.As for spam filters, it is difficult to say how they treat it, this is a local policy configuration.