Re: named + virtual domains

[Craig Sanders <cas@taz.net.au>]

On Fri, Oct 03, 2003 at 08:01:28PM +0200, Ralf G. R. Bergs wrote:
> You MUST NOT have multiple PTR records for the same IP. This is an error.

no it is not.  multiple PTR records are perfectly valid and are standard usage.

in fact, if you have multiple A records (note, not CNAME) pointing to 1 IP address
then you *should* have a corresponding PTR record for *each* A record.

i.e. if you have

a.example.com IN A 192.168.1.1
b.example.com IN A 192.168.1.1
c.example.com IN A 192.168.1.1
d.example.com IN A 192.168.1.1
e.example.com IN A 192.168.1.1

then the zone file for 1.168.192.in-addr.arpa *should* contain something like this:

1 IN PTR a.example.com.
1 IN PTR b.example.com.
1 IN PTR c.example.com.
1 IN PTR d.example.com.
1 IN PTR e.example.com.



this can be a PITA to keep updated, so it is often better to have just one A
record (and corresponding PTR record), and use CNAMEs for all other hostnames.

e.g.

a.example.com IN A 192.168.1.1
b.example.com IN CNAME a.example.com.
c.example.com IN CNAME a.example.com.
d.example.com IN CNAME a.example.com.
e.example.com IN CNAME a.example.com.

and in the in-addr.arpa zone:

1 IN PTR a.example.com.



please acquire a clue before dispensing advice.  start by reading _DNS & Bind_

craig