Spotty Lookups on One of Our Networks

Martin McCormick martin at dc.cis.okstate.edu
Tue Oct 30 20:10:34 UTC 2012


	I don't thing this is a bind problem because this
particular network has some Microsoft DNS's that are doing
exactly the same thing.

	There are several domains names that are broken in this
network and the symptome is always the same:

	Dig +trace @localhost one.bad.domain.com.

	We see all the root name servers listed. We get the TLD
servers next and, from one of them, we get authoritative DNS's
from bad.domain.com where we should get the IP address from
one.bad.domain.com. That is where it breaks. It times out with
no authoritative servers that will talk to us. One site is
noaa.gov which is the National Oceanic and Atmospheric
Administration in the United States.

	We have no trouble at all resolving them from our
network so I filled in the missing information for the
authoritative domain name servers and hard-coded one or two of
them in lookups on the problem network and, no surprise, the
lookup still times out.

	One really good lead evaporated when I discovered that
this network still had a 512-byte limit on its firewall so we
thought this might be the problem but no such luck. The firewall
now passes edns packets just fine, but nothing has really
changed.

	Any ideas as to what prevents some lookups from
resolving. Others do resolve.

	We have been kicking this problem around for about a
week and the customers, there, are getting a bit restless. They
are connected to the same ISP we are and we are not having any
problems like this. 

	There seems to be no reason  why some remote domains
work and others don't. I am asking on this list in hopes that
somebody has seen something like this somewhere else and found
the cause.

Thank you.

Martin McCormick WB5AGZ  Stillwater, OK 
Systems Engineer
OSU Information Technology Department Telecommunications Services Group



More information about the bind-users mailing list