Configuring Reverse Dns zone file

[Kevin Darcy]

Chris Ngo wrote:

>Hi all,
>
>Im trying to set my reverse dns. I have set my RDNS zone files, but
>when I dig my ip its doesnt show any of my PTR record.
>
>[root at octopusmarketing pz]# cat 193.204.161.209.in-addr.arpa 
>$TTL 86400
>
>@       IN      SOA     octopusmarketing.com.    cngo.emaylme.com. (
>                        1       ; Serial
>                        8H      ; Refresh
>                        2H      ; Retry
>                        1W      ; Expire
>                        1D)     ; Minimum TTL
>                NS      ns.octopusmarketing.com.
>
>1       IN      PTR     mail.investimmo.ca.
>2       IN      PTR     mail.adjointeplus.ca.
>
>
>
>when using the dig command, no PTR records appear:
>wasabi at acura wasabi $ dig @209.161.204.193 -x 209.161.204.193
>
>; <<>> DiG 9.2.2rc1 <<>> @209.161.204.193 -x 209.161.204.193
>;; global options:  printcmd
>;; Got answer:
>;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 13666
>;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL:
>0
>
>;; QUESTION SECTION:
>;193.204.161.209.in-addr.arpa.  IN      PTR
>
>;; AUTHORITY SECTION:
>193.204.161.209.in-addr.arpa. 86400 IN  SOA     octopusmarketing.com.
>cngo.emaylme.com. 1 28800 7200 604800 86400
>
>;; Query time: 62 msec
>;; SERVER: 209.161.204.193#53(209.161.204.193)
>;; WHEN: Sun Jul 18 15:10:05 2004
>;; MSG SIZE  rcvd: 115
>
I'm assuming the zone name is 193.204.161.209.in-addr.arpa. If that 
assumption is correct, then anything you put in the zone file will be 
relative to that name (unless overridden with an $ORIGIN directive). It 
would appear that you have in effect defined the records 
1.193.204.161.209.in-addr.arpa and 2.193.204.161.209.in-addr.arpa. Given 
that those would correspond to 5-octet reverse lookups, this is probably 
not what you wanted. More importantly, it looks like 
193.204.161.209.in-addr.arpa has not been delegated to your nameservers, 
so even if you were to define a "192.204.161.209.in-addr.arpa" PTR in 
that zone, no-one querying from the Internet would ever see it. It's not 
in the delegation chain down from the root zone, arpa, in-addr.arpa and 
so forth.

I think you and your ISP need to go back to the drawing board and figure 
out how you want/expect this delegation of control to work. The basic 
alternatives are either to delegate each address as a separate zone, or 
to go with the RFC 2317 "classless delegation" methodology of putting 
the PTRs in a "container" zone and then pointing aliases from the 
regular reverse zone to those PTRs.

                                                                         
                        - Kevin