Multiple PTR records

[Brad Knowles]

At 9:43 AM +0100 6/7/01, Marc Thach Xuan Ky wrote:

>  Then there was a similar thread in Dec 99, and a few references in Oct 99.
>  The consensus seems to be that it's best not to add multiple PTR records.

	Yup.  While technically legal, most applications don't deal with them well.

>  All well and good but how do I select which domain name to use in the
>  single PTR record?  Nobody seemed to touch on this.  It needs to be a
>  pragmatic decision, but in the absense of mail servers, where I'm not
>  expecting anybody to be using r-utilities, what other criteria should
>  I be looking at?

	Select one name to be the "canonical" name for that machine, and 
that's the one that gets used in the PTR record.  This would 
typically be the name you want the machine known by, if it ever has 
to do anything involving creating any connections to any other 
servers (as opposed to simply responding to connection attempts).

	So, for example, if this machine is a nameserver or a mail 
server, pick whichever name you want the outside world to know the 
machine by, and that is what gets used.  Everything else has a 
forward record, but no reverse (because the reverse is handled 
elsewhere).

-- 
Brad Knowles, <brad.knowles at skynet.be>

/*        efdtt.c  Author:  Charles M. Hannum <root at ihack.net>          */
/*       Represented as 1045 digit prime number by Phil Carmody         */
/*     Prime as DNS cname chain by Roy Arends and Walter Belgers        */
/*                                                                      */
/*     Usage is:  cat title-key scrambled.vob | efdtt >clear.vob        */
/*   where title-key = "153 2 8 105 225" or other similar 5-byte key    */

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