nanog mailing list archives
Re: Mailserver requirements
From: Valdis.Kletnieks () vt edu
Date: Mon, 05 Apr 2004 17:21:21 -0400
On Mon, 05 Apr 2004 23:03:05 +0200, Arnold Nipper <arnold () nipper de> said:
Today I run across a MTA which refused to accept mail because it could not detect an MX record for the reverse mapping of the IP address of the server which tried to deliver mail. Is this correct?
Depends on your definition of "correct". Checking that there's a PTR and A record that match has become common, although not strictly standard. Checking that said PTR points to a hostname that has an MX is certainly "way out there".
Or: if A is the IP Address of server trying to deliver mail, does mx(reverse(A)) have to exist?
There's no RFC requirement that an MX exist at all (only that you check for an MX before using the A record). The last 2 AOL boxes I got mail from were omr-m07.mx.aol.com and rly-ye05.mail.aol.com. I'm not seeing an MX for either of those. Draw your own conclusions as to whether a Randy Bush quote is needed....
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Current thread:
- Mailserver requirements Arnold Nipper (Apr 05)
- Re: Mailserver requirements Niels Bakker (Apr 05)
- Re: Mailserver requirements Valdis . Kletnieks (Apr 05)
- Re: Mailserver requirements Charles Sprickman (Apr 05)
- Re: Mailserver requirements Peter Galbavy (Apr 06)
- <Possible follow-ups>
- RE: Mailserver requirements Mike Walter (Apr 05)
- Re: Mailserver requirements Arnold Nipper (Apr 05)
- Re: Mailserver requirements Daniel Roesen (Apr 05)
- Re: Mailserver requirements Arnold Nipper (Apr 05)
- Re: Mailserver requirements Daniel Roesen (Apr 05)
- Re: Mailserver requirements Jim Segrave (Apr 06)
- Re: Mailserver requirements Arnold Nipper (Apr 05)
- Re: Mailserver requirements Valdis . Kletnieks (Apr 05)
- Re: Mailserver requirements Richard Welty (Apr 05)