Search Again: Re: Multiple CNAMES... who cares? From: andrew kagan Date: Thursday, July 29, 1999 Time: 12:57:00 pm Well, what's worse, redundant A records or multiple CNAME's? For example, I have my secondary dns on the same machine as my secondary mailserver. Right now, I have it set up like so: mydomain.com. NS ns2.mydomain.com. ns2.mydomain.com. A 198.0.0.0 mydomain.com. MX mail.mydomain.com mail.mydomain.com CNAME 198.0.0.0 Should the mailserver record be an A or CNAME in this case? ----- Original Message ----- From: Men & Mice Support <cbuxton@menandmice.com> To: QuickDNS Talk <quickdns-talk@lists.menandmice.com> Sent: Thursday, July 29, 1999 7:09 AM Subject: Re: Multiple CNAMES... who cares? > >Please explain to me why multiple CNAMES are "a bad thing." Here's what I > >have: > > > >In the "bigcitybaby.com." domain: > > > >yosemite.bigcitybaby.com. A 207.226.9.115 > >www.bigcitybaby.com CNAME yosemite.bigcitybaby.com > >etc. > > > >And in the "propressinc.com." domain: > > > >www.propressinc.com. CNAME yosemite.bigcitybaby.com. > >ftp.propressinc.com. CNAME yosemite.bigcitybaby.com. > >mail.propressinc.com CNAME yosemite.bigcitybaby.com. > >etc. > > > >What did I do wrong? And if I didn't do anything wrong, why is this > >considered an error in the QuickDNS log? > > The records above, by themselves, do not constitute an error (aside from > the missing period on mail.propressinc.com). > > However, given such records, the following would be an error: > propressinc.com. MX 10 mail.propressinc.com. > > It is against the rules to have any hostname that appears as data in a > record to have a CNAME record instead of an A record. The exception is > another CNAME (chaining CNAMEs), but even that is generally considered bad > practice. > > Furthermore, I checked your zone data. The following records constitute two > errors: > bigcitybaby.com. NS dns.bigcitybaby.com. > dns.bigcitybaby.com. CNAME yosemite.bigcitybaby.com. > bigcitybaby.com. CNAME yosemite.bigcitybaby.com. > > The first two records create an error, for the reason stated above. > > The last of these records is an error all by itself. It is agasint the > rules to have a CNAME record for any name that also has either other > records of the same name (such as the first of these three records) or has > subdomains (such as the second of these three records). > > Similarly, this record from your propressinc.com file also creates an error: > propressinc.com. CNAME yosemite.bigcitybaby.com. > > It's complications like this that lead me to almost never use CNAME > records. The solution is to use multiple A records for the same address. If > you then analyze your domain with DNS Expert, you'll see PTR record > "errors"; ignore them. > > I hope this helps. > ____________________________________________________________________ > Chris Buxton Men & Mice > cbuxton@menandmice.com http://www.menandmice.com >

Messages In This Thread: Multiple CNAMES... who cares? by Jimi Sweet on Jul 29, 1999 at 10:32:00 am Re: Multiple CNAMES... who cares? by Men & Mice Support on Jul 29, 1999 at 11:09:00 am Re: Multiple CNAMES... who cares? by Steve Linford on Jul 29, 1999 at 11:27:00 am Re: Multiple CNAMES... who cares? by andrew kagan on Jul 29, 1999 at 12:57:00 pm Re: Multiple CNAMES... who cares? by Men & Mice Support on Jul 30, 1999 at 8:21:00 am Re: Multiple CNAMES... who cares? by andrew kagan on Jul 30, 1999 at 12:23:00 pm Re: Multiple CNAMES... who cares? by Men & Mice Support on Jul 30, 1999 at 12:34:00 pm Re: Multiple CNAMES... who cares? by andrew kagan on Jul 30, 1999 at 1:14:00 pm Re: Multiple CNAMES... who cares? by Men & Mice Support on Jul 30, 1999 at 1:38:00 pm Re: Multiple CNAMES... who cares? by andrew kagan on Jul 30, 1999 at 2:14:00 pm Re: Multiple CNAMES... who cares? by Mia''s Virtual Post Office on Jul 30, 1999 at 5:59:00 pm Re: Multiple CNAMES... who cares? by Mia''s Virtual Post Office on Jul 30, 1999 at 6:02:00 pm Re: Multiple CNAMES... who cares? by Men & Mice Support on Jul 30, 1999 at 10:56:00 pm Re: Multiple CNAMES... who cares? by Men & Mice Support on Jul 30, 1999 at 11:10:00 pm