PTR records

[Kevin Darcy]

It *is* cleaner. If the address changes, you only have to change it in one
place. And there's no ambiguity about where the PTR should point. The only
time you have no choice about whether to use a CNAME or an A record is when
you're trying to make a name resolve to an IP address and it also happens to
be the name of a zone, e.g. example.com. You have to use an A record then,
since a CNAME can't co-exist with the records associated with the zone (SOA,
NS). Whenever there's a choice, though, CNAMEs tend to be the preferred
method.


- Kevin

Michele Chubirka wrote:

> The CNAME record is for that purpose. Why does it show up as an error if a
> DNS database has multiple A records for one IP address in most DNS
> diagnostic tools? Why even have CNAME records. While Bind may still work,
> the RFCs still seem to imply that it's cleaner to use one A name per IP and
> CNAMES referring to the A record.
>
> -----Original Message-----
> From: bind-users-bounce at isc.org [mailto:bind-users-bounce at isc.org]On
> Behalf Of Len Conrad
> Sent: Wednesday, September 27, 2000 7:03 PM
> To: bind-users at isc.org
> Subject: RE: PTR records
>
> >I thought it was very BAD form to have two A records pointing to the same
> >IP. You're not supposed to do this, it's a conflict, right?
>
> no, how do you think 100's of virtual www servers and smtp servers
> share the same ip?
>
> It's such good form that the ARIN/RIPE ip authorities encourage it heavily.
>
> Len