> The statement you're replying to doesn't say anything about the HELO > string. It says the PTR and A records should match (and they SHOULD).
Oh, come on. Which RFC states that? > This doesn't bother virtual domains at all. > > For example: > > IP addr A.B.C.D might have a PTR return "virtdomains.domain.tld" > > virtdomains should have an A record returning A.B.C.D (perhaps among > other IP addrs). But there may be more zones with an A record returning A.B.C.D. That's how a domain is virtualized. > The virtual domains can also have A records that say A.B.C.D. That > works, and doesn't violate the "PTR and A records should match" guideline. Who did sell you these guidelines? > And, in any case, the HELO string can be anything. It can be > virtdomains.domain.tld, or it can be one of the virtual domains, and > nothing should be wrong. HELO/EHLO must indicate the MTA official name. Maybe that the SMTP rfc doesn't clearly states that, but the DSN rfcs do state that, under the smtp domain, the name of a MTA must be a name mapping to the IP address of the MTA itself. This means that is must be the dns name or the ip address of the MTA. > And it wont violate the "PTR and A records > should match" guideline. Technically, it can be garbage, and still be > ok. Whatever it is, it doesn't change the item you replied to. Again, I can't recall a single RFC asserting that an A record must mutually map a PTR record. > > ...omissis... > > (but if they send email directly to me, instead of through their ISP, I > will reject them, because their customer oriented IP address shouldn't > be directly submitting email to my mail server) This is clearly stated in RFC 101974192374. :) You're "their ISP", isn't it? giampaolo
