reverse lookup on local IP (10.0.0.1)?

[alex]

Does anyone know whether I should be able to nslookup my local IP?

I have a small network set up as 10.x.x.x, and dial in to an ISP.
My caching nameserver is on 10.0.0.1.
If I try (from the 10.0.0.1 machine) to nslookup 10.0.0.1, I get:

-> Server: localhost
-> Address: 127.0.0.1

-> *** localhost can't find 10.0.0.1: Non-existent host/domain

Shouldn't I be able to resolve 10.0.0.1 to a name?

Here's /etc/resolv.conf:
order hosts,bind
multi on

Here's /etc/hosts:
127.0.0.1 localhost mydnshost.mydom.org
10.0.0.1 mydnshost.mydom.org mydnshost
10.0.0.2 otherhost.mydom.org otherhost


Thanks for your help.
--
Alex <alexkrowitz at my-dejanews.com>


Sent via Deja.com http://www.deja.com/
Before you buy.

[Barry Margolin]

In article <80gq0s$ek4$1 at nnrp1.deja.com>,

Post by alex
Does anyone know whether I should be able to nslookup my local IP?
I have a small network set up as 10.x.x.x, and dial in to an ISP.
My caching nameserver is on 10.0.0.1.
-> Server: localhost
-> Address: 127.0.0.1
-> *** localhost can't find 10.0.0.1: Non-existent host/domain
Shouldn't I be able to resolve 10.0.0.1 to a name?

You need to make your caching server authoritative for the 10.in-addr.arpa
reverse zone, and add a PTR record for its own address. It won't be able
to do this by its normal caching scheme, because the public delegation of
that reverse domain obviously won't point to servers that list your
machines.

[alex]

Thank you very much for your help. That did the trick! Does this mean
that reverse lookup does not make use of /etc/hosts?

In article <n5ZW3.20$KP4.837 at burlma1-snr2>,

Post by Barry Margolin
In article <80gq0s$ek4$1 at nnrp1.deja.com>,

Post by alex
Does anyone know whether I should be able to nslookup my local IP?
I have a small network set up as 10.x.x.x, and dial in to an ISP.
My caching nameserver is on 10.0.0.1.
-> Server: localhost
-> Address: 127.0.0.1
-> *** localhost can't find 10.0.0.1: Non-existent host/domain
Shouldn't I be able to resolve 10.0.0.1 to a name?

You need to make your caching server authoritative for the

10.in-addr.arpa

Post by Barry Margolin
reverse zone, and add a PTR record for its own address. It won't be able
to do this by its normal caching scheme, because the public delegation of
that reverse domain obviously won't point to servers that list your
machines.
--
Barry Margolin, barmar at bbnplanet.com
GTE Internetworking, Powered by BBN, Burlington, MA
*** DON'T SEND TECHNICAL QUESTIONS DIRECTLY TO ME, post them to newsgroups.
Please DON'T copy followups to me -- I'll assume it wasn't posted to the group.

--
Alex <alexkrowitz at my-dejanews.com>


Sent via Deja.com http://www.deja.com/
Before you buy.

[Richard Barnes]

10.X.X.X is a non-routable IP address.

Unless you ran a local DNS deamon and have a 0.0.10.in-addr.arpa entry, you
should not be able to find any entires for a 10.x.x.x IP address.

I say "local DNS deamon" because there is absolutely no reason for an ISP to
do reverse DNS lookups on any non-routable IP addresses. (10.x.x.x,
172.x.x.x, and 192.168.x.x)

Post by alex
Shouldn't I be able to resolve 10.0.0.1 to a name?

no...

your connection to the ISP is probably some form of NAT translation.
Meaning your caching server has two IP addresses on it (a real one, and the
non-routable one 10.0.0.1), anytime one of you workstations requests an
Internet resource (webpage, newsgroup, etc.) your caching server does the
actualy request for you, and then sends the returned info to the client who
originally requested it.

Is there a reason you want reverse DNS setup? If you are getting errors
when surfing, indicating that reverse DNS is not enabled, perhaps you should
contact you ISP and have them setup a reverse lookup entry for the IP
address of your caching server (the real, routable one).

-----Original Message-----
From: alex <alexkrowitz at my-deja.com>
Newsgroups: comp.os.linux.networking;,comp.protocols.dns.bind
To: comp-protocols-dns-bind at moderators.isc.org
<comp-protocols-dns-bind at moderators.isc.org>
Date: Friday, November 12, 1999 11:27 AM
Subject: reverse lookup on local IP (10.0.0.1)?

Post by alex
Does anyone know whether I should be able to nslookup my local IP?
I have a small network set up as 10.x.x.x, and dial in to an ISP.
My caching nameserver is on 10.0.0.1.
-> Server: localhost
-> Address: 127.0.0.1
-> *** localhost can't find 10.0.0.1: Non-existent host/domain
Shouldn't I be able to resolve 10.0.0.1 to a name?
order hosts,bind
multi on
127.0.0.1 localhost mydnshost.mydom.org
10.0.0.1 mydnshost.mydom.org mydnshost
10.0.0.2 otherhost.mydom.org otherhost
Thanks for your help.
--
Alex <alexkrowitz at my-dejanews.com>
Sent via Deja.com http://www.deja.com/
Before you buy.

[Joseph S D Yao]

Post by alex
Does anyone know whether I should be able to nslookup my local IP?
I have a small network set up as 10.x.x.x, and dial in to an ISP.
My caching nameserver is on 10.0.0.1.
-> Server: localhost
-> Address: 127.0.0.1
-> *** localhost can't find 10.0.0.1: Non-existent host/domain
Shouldn't I be able to resolve 10.0.0.1 to a name?

I just re-posted (under 'Re: nslookup') a discussion of reverse DNS.
Read and do.