[Cialug] DNS Reverse Lookup

[Tom Sellers]

I can't say since I am very new to working with DNS.  I don't have the opportunity to work with this at work since all that is done by our corporate support group.  That is why I was trying to learn something about it by setting one up at home.  

I did learn some additional information that I don't know if is significant this morning.  Most of my testing has been done from the actual machine that is running the DNS.  When I do an nslookup on that machine for example my local gateway (idendified as "gw") is resolved right away.  However, if I go to a separate workstation and peform a ping command (ping gw) it does not resolve.  If I give it a fully qualified domain name (ping gw.mydomain.com) though it resolves immediately.

Is there anyone with a good knowledge of DNS that can give me some guidance on my setup?  I am running Ubuntu 8.10 on the machine and bind9. I have my DNS set up to forward to my ISP if the name does not resolve. I can browse the internet so I am getting resolution to outside web sites properly.  Directory structure is /etc/bind and below that /etc/bind/zones.  There are both a forward and reverse lookup in the zones directory.  

--- On Fri, 5/15/09, Matthew Lechleider <matthew at lechleider.com> wrote:

> From: Matthew Lechleider <matthew at lechleider.com>
> Subject: Re: [Cialug] DNS Reverse Lookup
> To: "Central Iowa Linux Users Group" <cialug at cialug.org>
> Date: Friday, May 15, 2009, 11:52 PM
> I received the same response.
> 
> Is there a standard response for reverse lookups on
> internally reserved 
> address space?
> 
> Does your computer know to look at your local namserver and
> not a public 
> Internet nameserver?
> 
> 
> Tom Sellers wrote:
> > Here is the response to using the command that you
> suggested.  Since I'm new to this I'm not sure what the
> below tells me.  The section under Authority Section
> looks a little questionable but not sure what it should look
> like.
> >
> > Does this tell you anything of value?
> >
> > tsellers at bluto-laptop:~$ dig -x 192.168.1.1
> >
> > ; <<>> DiG 9.5.0-P2 <<>> -x
> 192.168.1.1
> > ;; global options:  printcmd
> > ;; Got answer:
> > ;; ->>HEADER<<- opcode: QUERY, status:
> NXDOMAIN, id: 62144
> > ;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1,
> ADDITIONAL: 0
> >
> > ;; QUESTION SECTION:
> > ;1.1.168.192.in-addr.arpa.   
> IN    PTR
> >
> > ;; AUTHORITY SECTION:
> > 168.192.in-addr.arpa.   
> 10800    IN   
> SOA    prisoner.iana.org.
> hostmaster.root-servers.org. 2002040800 1800 900 604800
> 604800
> >
> > ;; Query time: 486 msec
> > ;; SERVER: 192.168.1.9#53(192.168.1.9)
> > ;; WHEN: Fri May 15 23:36:23 2009
> > ;; MSG SIZE  rcvd: 119
> >
> >
> > --- On Fri, 5/15/09, Matthew Lechleider <matthew at lechleider.com>
> wrote:
> >
> >   
> >> From: Matthew Lechleider <matthew at lechleider.com>
> >> Subject: Re: [Cialug] DNS Reverse Lookup
> >> To: "Central Iowa Linux Users Group" <cialug at cialug.org>
> >> Date: Friday, May 15, 2009, 11:33 PM
> >> Try dig with the flag -x for reverse
> >> lookup.
> >>
> >> dig -x IP
> >>
> >>
> >> Tom Sellers wrote:
> >>     
> >>> I have set up a DNS server on my home network
> and
> >>>       
> >> although it resolves machine names to IP addresses
> just fine
> >> I can't seem to make it perform the reverse
> lookup
> >> properly.
> >>     
> >>> Below is an example and the DIG information on
> my DNS
> >>>       
> >> server.
> >>     
> >>> Can anyone shed some light on where I have
> gone wrong
> >>>       
> >> here?
> >>     
> >>>       
> >>
> ------------------------------------------------------------------------
> >>     
> >>> tsellers at bluto-laptop:~$ nslookup gw
> >>> Server:       
> >>>       
> >> 192.168.1.9
> >>     
> >>> Address:    192.168.1.9#53
> >>>
> >>> Name:    gw.mydomain.com
> >>> Address: 192.168.1.1
> >>>
> >>> tsellers at bluto-laptop:~$ nslookup 192.168.1.1
> >>> Server:       
> >>>       
> >> 192.168.1.9
> >>     
> >>> Address:    192.168.1.9#53
> >>>
> >>> ** server can't find
> 1.1.168.192.in-addr.arpa.:
> >>>       
> >> NXDOMAIN
> >>     
> >>> tsellers at bluto-laptop:~$ dig mydomain.com
> >>>
> >>> ; <<>> DiG 9.5.0-P2
> <<>>
> >>>       
> >> mydomain.com
> >>     
> >>> ;; global options:  printcmd
> >>> ;; Got answer:
> >>> ;; ->>HEADER<<- opcode: QUERY,
> status:
> >>>       
> >> NOERROR, id: 29703
> >>     
> >>> ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 0,
> AUTHORITY:
> >>>       
> >> 1, ADDITIONAL: 0
> >>     
> >>> ;; QUESTION SECTION:
> >>> ;mydomain.com.   
>    
> >>>       
> >>     IN    A
> >>     
> >>> ;; AUTHORITY SECTION:
> >>> mydomain.com.       
> >>>       
> >> 38400    IN   
> >> SOA    bluto.mydomain.com.
> >> admin.mydomain.com. 2007062001 28800 3600 604800
> 38400
> >>     
> >>> ;; Query time: 1 msec
> >>> ;; SERVER: 192.168.1.9#53(192.168.1.9)
> >>> ;; WHEN: Fri May 15 23:17:25 2009
> >>> ;; MSG SIZE  rcvd: 78
> >>>
> >>>
> >>>
> >>>        
> >>>
> >>>
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> >>     
> >
> >
> >       
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