Les Mikesell wrote:
Nick Leverton wrote:
I'm not sure which part of RFC 2821 you're referring to when you talk
about "breaking SMTP" in the context of rDNS checking.
4.1.4
"An SMTP server may verify that the domain name parameter in the EHLO
command actually corresponds to the IP address of the client. However,
the server must not refuse to accept a message for this reason if the
verification fails: the information about verification failure is for
logging and tracing only."
Even Dave Crocker admits that this was written in a far less hostile
environment than today's internet. I've been in talks where he's said as
much, and I've had lunch with him where he's said similar.
Matt.
