Is this correct behaviour?

[Anand S Medikeri]

 Sorry for bothering again.  

 As far I know  in-addr.arpa  domain maps IP addresses to hostnames.  If
 my   understanding   is  true  then  it  dosen't  make  sense  to  load
 6.5.4.3.2.in-addr.arpa RR since a host cannot have 1.2.2.3.4.5.6 as its
 IP address.  And if it takes it to be CIDR than why is it not ture with
 A RR which when has data portion as  1.2.2.3.4.5.6  says not a valid IP
 addr.

 I am using nslookup to get the PTR records. For

 nslookup -type=ptr 1.2.3.4 
 I get an answer and for
 nslookup -type=ptr 1.2.2.3.4.5.6 
 I get an error message. So which one to fix nslookup or named.

 Please correct me if my understanding about in-addr.arpa is wrong.

Thanx.


> >>>>> "Anand" == Anand S Medikeri <anandsm at manohari.india.hp.com> writes:
> 
>     Anand> I am using bind 8.1.2. I have an entry in named.conf for zone
>     Anand> 1.2.IN-ADDR.ARPA as below
> 
>     Anand> ;db.1.2      *******************************************
>     Anand> @       IN      SOA     a.b.c.d. root.a.b.c.d. (
>     Anand> 1       ; Serial
>     Anand> 10800   ; Refresh every 3 hours
>     Anand> 3600    ; Retry every hour
>     Anand> 604800  ; Expire after a week
>     Anand> 86400 ) ; Minimum ttl of 1 day
>     Anand> IN      NS      a.b.c.d.
>  
>     Anand> 3.4    IN      PTR	hello.b.c.d.
>     Anand> 6.5.4.3.2 IN   PTR     world.b.c.d.
> 
>     Anand> All RR's  seems to be loaded by the  server.  when I query
>     Anand> the  server with type set to PTR and question to
>     Anand> 6.5.4.3.2.2.1.in-addr.arpa.  I get the RR in reply. 
>     Anand> Should I get that reply ?
> 
> Yes. You asked for some resource record from the DNS. The name of that
> resource record was in the DNS, so you got an answer with valid data
> returned. That's what name servers do with valid queries from
> resolvers... :-) Whether the name being queried is sensible or not is
> another story.
> 
> As the owner of the 2.1.in-addr.arpa zone ut's up to you to decide if
> the name 6.5.4.3.2.2.1.in-addr.arpa should be in that zone and, if so,
> what it should point at. Since PTR records are usually in the form
> A.B.C.D.in-addr.arpa, the entry in your zone file is probably
> wrong. You've entered a PTR record for 6.5.4.3.2.2.1.in-addr.arpa in
> the zone file, so I presume you must have your own reasons for wanting
> this.
>