Two queries: directory hashing and recursive queries

[David Botham]

> -----Original Message-----
> From: bind-users-bounce at isc.org [mailto:bind-users-bounce at isc.org] On
> Behalf Of John Ekins
> Sent: Friday, January 17, 2003 7:41 AM
> To: comp-protocols-dns-bind at isc.org
> Subject: Two queries: directory hashing and recursive queries
> 
> 
> Hello,
> 
> I've already asked one of my questions on questions at freebsd.org, so
> apologies if you read it there.
> 
> Firstly directory hashing: I have a question about "best" practices
for
> directory hashing. I have about 80,000 zone files which are named
after
> the domain which I generate using a Perl script. I'm looking for the
> best hashing to reduce the start up time for bind.
> 
> I've tried different hashings. Using example.foo as an example (:-)),
if
> I take the first and second letters of the domain and hash it like
this
> /var/named/e/x/example.foo I still end up with (in a few cases) more
> than 3000 zones in one directory. If I hash using the first+second and
> third+fourth like this /var/named/ex/am/example.com I end up with a
lot
> fewer zones in the individual directories, but bind's start up time is
> much longer.
> 
> I can live with the first hashing if I need to, but I'm seeking some
> advice and suggestions on what others think (or know) would be better.
> 
> It was suggested in the FreeBSD group to hash with last and second to
> last letter, which should be more random, and also to use FreeBSD's
ufs
> directory hashing. I actually have that enabled anyway.
> 
> 
> My second question is about bind 9 on a Sun with two processors. If I
> build bind --with-threads, with recursion turned off I get no response
> at all from bind. If I build bind without that build option, again
with
> recursion turned off, I get the list of root name servers. Why does
bind
> do this? It's not a problem as such, just an observation.

Not sure about the threads / no threads thingy.

However, if you turn off recursion and ask bind about a zone for which
it is not authoritative, it will return a referral.  Sometimes the best
answer you will get is to the root or gtld name servers.

Dave...

> 
> Thanks,
> John.