[ale] Re: nslookup

[marct at mindspring.com (Marc Torres)]

Matthew Avery wrote:

> >From miranda (Linux machine at my desk):
> 
> miranda 38# nslookup - 192.92.183.13
> *** Can't find server name for address 192.92.183.13: No response from server
> *** Default servers are not available
> miranda 39# nslookup - 129.99.35.1

> 
> For some reason I can't *start* nslookup with the default
> nameserver for miranda but if I start it with another
> nameserver and then switch it works fine.  Very strange.
> 
> -Matt-
> 
Matt, it doesn't appear that the nameserver 192.92.183.13 can reverse
map its own ip.  I just checked and 13.183.92.192.in-addr.arpa. does
not exist!

The nameservers responsible for 183.92.192.in-addr.arpa. are:
data.nas.nasa.gov
imp.nas.nasa.gov
fs01.nas.nasa.gov

Nslookup it programmed to first reverse map the server IP its given
before it does anything else...  Resolver libraries (the guys who
do name resolution for ping, telnet, etc) don't bother to do this,
and this is why normal programs work.

When nslookup fails to reverse the IP of a server, it won't talk to it.

If I didn't word this clearly just yell at me and I'll write another
(and take more then 2 or 3 mins to do so ;-)

Marc Torres