DNS beginner - looking for advice

[Kevin Darcy]

1. Technically, you should not be pointing PTRs at CNAMEs; they should only
point to "canonical" names. So the PTR for 1.0.168.192.in-addr.arpa should be
pointing to ns.ip-143-191.gw.total-web.net. instead of
ghost.ip.143-191.gw.total-web.net.

2. Were you expecting other nodes on the 192.168.0/24 network -- wilson,
billybob, mario, etc. -- to reverse-resolve? You haven't added records for them
into the 0.168.192.in-addr.arpa zone (the PTR pointing to
wilson.ip-143-191.gw.total-web.net appears to be misplaced; seems like it
should be under 192.168.0.2, but you have it under 127.0.0.2).

3. The underscore in mxp_laptop is technically illegal. You could force named
to accept it by using the "check-names" option in either the
"options" statement or the zone statement.

Or is it the reverse-lookup of your *external* address that isn't working?
Since you have only one IP address, you'd need your provider to either delegate
that address as a separate zone to your server (wherein you'd add a PTR for
that address), or to have them add a CNAME in their reverse zone pointing to a
PTR in a zone you control (see RFC 2317 to get the gist of the latter option).


- Kevin

The Dude wrote:

> I have a cable modem with a single static ip address. I have a RedHat 6.2
> box doing routing via ipchains for my internal network 192.168.0. I've setup
> dns on the linux box to handle my internal requests more quickly and I also
> wanted it to resolve my interal names. By reading the HOWTO's and this
> newsgroup, I've gotten most if this to work except for the darned REVERSE
> LOOKUP. But in the process, I've mucked up my configuretion files with
> surperflous zones. I was looking for advise on what I need to get this
> configuration working. Here are my current files.
>
> /etc/named.conf
>  options {
>  directory "/var/named";
>         forward first;
>         forwarders {
>              209.186.12.2;
>              209.186.12.3;
>         };
> };
> zone "." {
>  type hint;
>  file "named.ca";
> };
> zone "0.0.127.in-addr.arpa"{
>  type master;
>  file "127.0.0";
> };
> zone "ip-143-191.gw.total-web.net" {
>         notify no;
>         type master;
>         file "ip-143-191.gw.total-web.net";
> };
> zone "0.168.192.in-addr.arpa" {
>   type master;
>  file "192.168.0";
>         allow-query { 192.168.0/24; };
> };
>
> /var/named/127.0.0
> @               IN      SOA     ns.ip-143-191.gw.total-web.net.
> hostmaster.ip-14
> 3-191.gw.total-web.net. (
>                                 1       ; Serial
>                                 8H      ; Refresh
>                                 2H      ; Retry
>                                 1W      ; Expire
>                                 1D)     ; Minimum TTL
>                         NS      ns.ip-143-191.gw.total-web.net.
> 1                       PTR     localhost.
> 2                       PTR     wilson.ip-143-191.gw.total-web.net.
>
> /var/named/192.168.0
> @               IN      SOA     ip-143-191.gw.total-web.net.
> root.ip-143-191.gw.
> total-web.net. (
>                                 1       ; Serial
>                                 8H      ; Refresh
>                                 2H      ; Retry
>                                 1W      ; Expire
>                                 1D)     ; Minimum TTL
>                         NS      ns.ip-143-191.gw.total-web.net.
> 1               IN      PTR     ghost.ip.143-191.gw.total-web.net.
>
> /var/named/ip-143-191.gw.total-web.net
> ;
> ; Zone file for ip-143-191.gw.total-web.net
> ;
> ; The full zone file
> ;
> @       IN      SOA     ns.ip-143-191.gw.total-web.net.
> hostmaster.ip-143-191.gw
> .total-web.net. (
>                         199802151       ; serial, todays date + todays
> serial #
>                         8H              ; refresh, seconds
>                         2H              ; retry, seconds
>                         1W              ; expire, seconds
>                         1D )            ; minimum, seconds
> ;
>                 NS      ns              ; Inet Address of name server
>                 MX      10 mail.ip-143-191.gw.total-web.net.     ; Primary
> Mail
> Exchanger
> ;               MX      20 mail.friend.bogus.   ; Secondary Mail Exchanger
> ;
> localhost       A       127.0.0.1
> ns              A       192.168.0.1
>                 MX      10 mail
>                 HINFO   "K6" "Linux 2.2"
> mail            CNAME   ns
> ghost           CNAME   ns
>
> wilson          A       192.168.0.2
>
> billybob        A       192.168.0.4
> mxp_laptop      A       192.168.0.5
> mario           A       192.168.0.6
>
> Somebody please set me straight.
>
> TAI,
> Mario