Base domain resolution

[Joshua Smith]

A single A record for multiple hosts is perfectly fine.

On Wed, Feb 27, 2008 at 10:36 AM, Barry Finkel
<b19141 at britaine.cis.anl.gov> wrote:
> J <usenet at linuxnuts.net> wrote, in part:
>
>  >For years I've been taught to never put an A record on a base domain
>  >(domain.tld).  I know that just about every major domain does this
>  >these days but that doesn't make it right.  I'd like to be able to
>  >support my losing position with technical answers so I can point out
>  >the potential and future problems before they come back and bite us on
>  >the ass (a CYA measure for me since I know I will lose this fight).
>  >As I recall it, there were a number of technical reasons why one
>  >should not have the base domain resolve to anything but I'm afraid I
>  >no longer remember what all the reasons are any more.  A couple cheesy
>  >ones come to mind:
>
>  What about a domain that uses Windows Active Directory?  If the AD
>  domain is
>
>      example.com
>
>  then a query for "A" record for that domain will return the addresses
>  of all of that domain's Domain Controllers.  I am sure that there are
>  many domains on the Internet for which this is true.
>
>  Of course, if this is the case, then one cannot omit the "www."
>  prefix for
>
>      www.example.com
>
>  as I doubt that any knowledeable site would host a web server on
>  each Windows DC.
>  ----------------------------------------------------------------------
>  Barry S. Finkel
>  Computing and Information Systems Division
>  Argonne National Laboratory          Phone:    +1 (630) 252-7277
>  9700 South Cass Avenue               Facsimile:+1 (630) 252-4601
>  Building 222, Room D209              Internet: BSFinkel at anl.gov
>  Argonne, IL   60439-4828             IBMMAIL:  I1004994
>
>
>