davy@ERG.SRI.COM (10/30/90)
The question was: Should there be an A record for a domain name itself? Out of 26 responses, 17 said "yes", 7 said "no", and 2 were ambivalent. Some of the arguments/reasons were: PRO: - It's the machine which will accept mail for the entire domain, plus will accept FTP and TELNET connections. - Providing an A RR for the domain lets people with mailers that don't understand MX records still send mail to you. CON: - The lookup of the PTR record for this address won't match what you get via a forward lookup. [Well, it will give you the proper hostname of the machine instead of the domain name, but it's not like that's a *wrong* answer.] OTHER COMMENTS RECEIVED: - No real reason to do it unless you hide hosts in the domain. (I.e., send all mail as "From: user@domain" instead of "From: user@host.domain"). - A newer convention than FTP to the domain name is to have a CNAME for a host called "ftp" which points at the FTP host (e.g. ftp.uu.net). - Ohio State has 4 A RRs for their domain name; each identifies one of the central servers. [As I understand it, NFS and such make these machines all equivalent as far as network connections, FTP, etc. go.] - Some people made arguments based on whether there's actually a machine with that name. If so, then yes. If not, then no. [This seemed like sort of a weird argument to me - names are whatever you want them to be.] - A CNAME record for the domain is never appropriate. Thanks for all the responses. I've decided that at least for our domain, having an A record for the domain name is the Right Thing to do. --Dave Curry SRI International