-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu] Sent: Wednesday, December 01, 2004 12:57 PM To: nanog@merit.edu Subject: Re: is reverse dns required? (policy question)

...

I thought I saw some 'MUST' statements in an RFC

[*] From RFC 1912, section 2.1. http://www.faqs.org/rfcs/rfc1912.html

"Every Internet-reachable host should have a name. The consequences of this are becoming more and more obvious. Many services available on the Internet will not talk to you if you aren't correctly registered in the DNS.

Make sure your PTR and A records match. ... Failure to have matching PTR and A records can cause loss of Internet services similar to not being registered in the DNS at all. Also, PTR records must point back to a valid A record, not a alias defined by a CNAME."

I think it's best practice, even if not written. As far back as I can remember, you couldn't access ftp.uu.net without a proper reverse and that's probably going on 14 years or so. The relevance there is that it was considered proper that far back all the way to this day. Many services won't respond or allow without reverses either. As far as charging, I've seen ISP's set limits on how many changes a month. Not on establishing the records. They're a required part of the service - in my mind. -M<