Caching name server setup problems

[G.W. Haywood]

Hi there,

On Tue, 15 Jul 2008, Michael Varre wrote:

> ... I don't see that my server is actually caching anything.  I
> don't see where that cached data is being stored, and further more I
> don't see any difference in query answer time from the first time I
> try to resolve a host to any subsequent attempts.  they are ALL 1ms.

The cache is in RAM.  The current default cache size is 32MB, so you
could change that in the config (man named.conf) and see what happens
to the resources used by the named process.  You may be able to dump
the cache to disc with

rndc dumpdb

Try also just

rndc

for a bit of help.

You can play around with the settings e.g. to prevent certain hosts from
being supplied with cached information, to see what happens.  Search for
'cache' in

man named.conf

and in

http://www.isc.org/index.pl?/sw/bind/index.php

I wonder if your timings have sufficient precision and if you ensured
that the first query was not cached.

I strongly recommend the O'Reilly books:

http://www.oreillynet.com/pub/a/network/excerpt/dnsbindcook_ch05/?page=2
http://oreilly.com/catalog/9780596100575/index.html

(and I have no affiliation with O'Reilly... :)

--

73,
Ged.