Strange DNS resolving behavior

ngaccess at hotpop.com ngaccess at hotpop.com
Thu Apr 22 18:17:13 UTC 2004


Hi,

Your nameserver (148.85.1.1) resolves fine both forward and reverse from 
here when I do a lookup for amherst.publishingconcepts.com. No timeouts - 
looks normal. 

HTH

On 21 Apr 2004 at 10:31, John Manly wrote:
Subject:        	Strange DNS resolving behavior
Date sent:      	Wed, 21 Apr 2004 10:31:47 -0400
From:           	"John Manly" <jwmanly at amherst.edu>
To:             	<bind-users at isc.org>

> Greetings, all.  I'm experiencing a strange problem with DNS resolving
> that I'm hoping someone can shed some light on.  A vendor that we work
> with has set up a DNS name in their domain,
> "amherst.publishingconcepts.com" as an A record with an IP address of
> 12.156.3.83.  However, my site's DNS servers (and one other ISP's DNS
> servers that I can find) for some reason cannot resolve this address.
> But every other DNS server that I've tried querying can resolve the
> address.  Further, the problem appears to be specific to this particular
> name -- other A records in the same domain (such as
> www.publishingconcepts.com or tigernet.publishingconcepts.com) resolve
> properly.  I have no idea where to start looking for a solution (or even
> an explanation of this.)
> 
> Below are the results of some of my NSLOOKUP attempts to my own
> nameserver, as well as those of Genuity/Level3 (the other set of DNS
> servers that appear to be unable to resolve the name), and then a bunch
> from DNS servers that appear to work properly.
> 
> First, here are three tests against my own name server.  The problematic
> name produces a timeout, but another name within the same domain that I
> know is valid works properly, and an attempt to translate a name that I
> know doesn't exist gives the expected error result (but not a timeout).
> 
> 
> $ nslookup -q=3DA amherst.publishingconcepts.com 148.85.1.1  # My
> nameserver
> ;; connection timed out; no servers could be reached       # Timeout
> response
> 
> 
> $ nslookup -q=3DA www.publishingconcepts.com 148.85.1.1      # My
> nameserver, trying another name
> Server:         148.85.1.1
> Address:        148.85.1.1#53
> Non-authoritative answer:
> Name:   www.publishingconcepts.com=20
> Address: 12.156.3.116                                      # Looks like
> it worked properly
> 
> 
> $ nslookup -q=3DA foo.publishingconcepts.com 148.85.1.1      # My
> nameserver, a name I know doesn't exist
> Server:         148.85.1.1
> Address:        148.85.1.1#53
> ** server can't find foo.publishingconcepts.com: NXDOMAIN  # The
> expected error, not a timeout
> 
> 
> Next, here are a series of NSLOOKUPs of the problematic name against a
> series of other name servers, all of which appear to work fine:
> 
> 
> $ nslookup amherst.publishingconcepts.com 138.110.1.1      # Mount
> Holyoke College
> Server:         138.110.1.1
> Address:        138.110.1.1#53
> Non-authoritative answer:
> Name:   amherst.publishingconcepts.com
> Address: 12.156.3.83    # <------------------------------- Correct
> answer
> 
> 
> $ nslookup amherst.publishingconcepts.com 128.119.166.8    # University
> of Mass
> Server:         128.119.166.8
> Address:        128.119.166.8#53
> Non-authoritative answer:
> Name:   amherst.publishingconcepts.com
> Address: 12.156.3.83    # <------------------------------- Correct
> answer
> 
> 
> $ nslookup amherst.publishingconcepts.com 151.202.0.68     # Verizon New
> York DNS
> Server:         151.202.0.68
> Address:        151.202.0.68#53
> Non-authoritative answer:
> Name:   amherst.publishingconcepts.com
> Address: 12.156.3.83    # <------------------------------- Correct
> answer
> 
> 
> $ nslookup amherst.publishingconcepts.com 199.45.45.14     # Verizon
> Washington DC DNS
> Server:         199.45.45.14
> Address:        199.45.45.14#53
> Non-authoritative answer:
> Name:   amherst.publishingconcepts.com
> Address: 12.156.3.83    # <------------------------------- Correct
> answer
> 
> 
> $ nslookup amherst.publishingconcepts.com 192.9.9.3        # Sun
> Microsystems
> Server:         192.9.9.3
> Address:        192.9.9.3#53
> Non-authoritative answer:
> Name:   amherst.publishingconcepts.com
> Address: 12.156.3.83    # <------------------------------- Correct
> answer
> 
> 
> $ nslookup amherst.publishingconcepts.com 207.217.126.41   # Earthlink
> Server:         207.217.126.41
> Address:        207.217.126.41#53
> Non-authoritative answer:
> Name:   amherst.publishingconcepts.com
> Address: 12.156.3.83    # <------------------------------- Correct
> answer
> 
> 
> Finally, I ask Genuity/Level3's name servers.  Genuity/Level3 acts
> provides secondary name service for our domains.  In one case it reports
> the domain or name isn't valid, and in another it times out just like my
> own nameserver does. But again, when I look up a name within the
> publishingconcepts.com domain that I know doesn't exist, I get a
> different kind of error (the expected error) back:
> 
> 
> $ nslookup amherst.publishingconcepts.com 4.2.49.3         #
> Genuity/Level3
> Server:         4.2.49.3
> Address:        4.2.49.3#53
> Non-authoritative answer:
> *** Can't find amherst.publishingconcepts.com: No answer   # WRONG ANSER
> 
> 
> $ nslookup -q=3DA amherst.publishingconcepts.com 4.2.2.1     # Another
> Genuity/Level3 server
> ;; connection timed out; no servers could be reached       # No answer
> at all (timeout)
> 
> 
> $ nslookup -q=3DA foo.publishingconcepts.com 4.2.2.1         #
> Genuity/Level3 ISP DNS server
> Server:         4.2.2.1
> Address:        4.2.2.1#53
> ** server can't find foo.publishingconcepts.com: NXDOMAIN  # NXDOMAIN
> (no such name)
> 
> So, I'm completely stumped as to what is going on here.  Somehow this
> particular name "amherst.publishingconcepts.com" is not resolving via
> some DNS servers, specifically mine. But other names in the
> publishingconcepts.com domain are resolving properly, and the error that
> the above DNS name yields is different from the name simply being
> missing.
> 
> Any light that anyone can shed, or directions that anyone can sugggest
> for further debugging/troubleshooting/investigation on this issue would
> be most helpful.
> 
> -- John W. Manly  <jwmanly at amherst.edu>
>    Systems and Networking, Amherst College
> 
> 





More information about the bind-users mailing list