classless delegation [Re: IP address fee??]

Jeroen Massar jeroen at unfix.org
Fri Sep 6 20:28:58 UTC 2002


Brad Knowles wrote:

> At 4:40 PM +0200 2002/09/06, Peter van Dijk wrote:

It could be me but...

<SNIP>
> >>  o The reverse zone contains one or more A records
> >>      The reverse domain "192.122.109.193.in-addr.arpa." 
> contains one
> >>      or more A records.  A records should only be placed in
> >>      forward-mapping domains.
> >
> >  What A-records is it talking about? I am not seeing any.

Yes, they get returned, whoo hoo:
8<---------
jeroen at purgatory:~$ dig 192.122.109.193.in-addr.arpa any

; <<>> DiG 9.1.3rc3 <<>> 192.122.109.193.in-addr.arpa any
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 13829
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;192.122.109.193.in-addr.arpa.  IN      ANY

;; ANSWER SECTION:
192.122.109.193.in-addr.arpa. 66808 IN  NS      ns3.dataloss.nl.
192.122.109.193.in-addr.arpa. 66808 IN  NS      ns.dataloss.nl.

;; AUTHORITY SECTION:
192.122.109.193.in-addr.arpa. 66808 IN  NS      ns3.dataloss.nl.
192.122.109.193.in-addr.arpa. 66808 IN  NS      ns.dataloss.nl.

;; ADDITIONAL SECTION:
ns.dataloss.nl.         239655  IN      A       193.109.122.194
ns3.dataloss.nl.        66855   IN      A       193.109.122.215

;; Query time: 22 msec
;; SERVER: ::1#53(::1)
;; WHEN: Fri Sep  6 22:14:25 2002
;; MSG SIZE  rcvd: 152
--------->8

But isn't that normal for a zone?:

Let's take seque.merit.edu (just picked a host from the message headers
:)

8<---------------------------------
jeroen at purgatory:~$ dig 41.1.108.198.in-addr.arpa. any

; <<>> DiG 9.1.3rc3 <<>> 41.1.108.198.in-addr.arpa. any
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 13553
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 3, ADDITIONAL: 3

;; QUESTION SECTION:
;41.1.108.198.in-addr.arpa.     IN      ANY

;; ANSWER SECTION:
41.1.108.198.in-addr.arpa. 172786 IN    PTR     segue.merit.edu.

;; AUTHORITY SECTION:
1.108.198.in-addr.arpa. 172786  IN      NS      dns.merit.net.
1.108.198.in-addr.arpa. 172786  IN      NS      dns2.merit.net.
1.108.198.in-addr.arpa. 172786  IN      NS      dns3.merit.net.

;; ADDITIONAL SECTION:
dns.merit.net.          172794  IN      A       198.108.1.42
dns2.merit.net.         172794  IN      A       198.109.36.3
dns3.merit.net.         172794  IN      A       198.108.130.5

;; Query time: 7 msec
;; SERVER: ::1#53(::1)
;; WHEN: Fri Sep  6 22:17:55 2002
;; MSG SIZE  rcvd: 185
--------------------------------->8

Or any other IP you would randomly pick actually... show me one that
doesn't have this behaviour :)

What is so special about the reverse zones anyways?
You must be one very stupid implementor if you where handling those
zones
differently than 'forward' zones... Nothing wrong with putting up
something like:

60.1.0.10.in-addr.arpa. CNAME bla-reverse.example.org.
bla-reverse.example.org. PTR bla.example.org.
bla.example.org. A 10.0.1.60

What's wrong with that? No RFC against it ;)

> 	They are the ones associated with your NS records.  At a 
> procedural level, PTR records are mutually exclusive with SOA & NS 
> records.
You are actually saying that one can't setup a DNS for a reverse host
then ;)
Cool, why does it work then? <grin>

Btw... another 'cool' DNS tool: www.

Greets,
 Jeroen




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