named listening on UDP

[Mark Andrews]

> Was the original issue misstated?  You said it was "listening" on these
> ports.  Outbound queries wouldn't be "listening" - they'd simply be
> established when needed.

	TCP connections are established as needed.

	UDP sockets have to listen for replies.  Named uses the
	one socket to talk to remote nameservers.  For a nameserver
	with any sort of recursive load named would quickly exceed
	the OS's ability to supply sockets if it was to open a new
	socket for each nameserver it queries.
 
> -----Original Message-----
> From: bind-users-bounce at isc.org [mailto:bind-users-bounce at isc.org] On
> Behalf Of Tom Schmitt
> Sent: Wednesday, April 04, 2007 3:51 AM
> To: bind-users at isc.org
> Subject: Re: named listening on UDP
> 
> Thank you (and the others) for your answers. This helps me.
> Tom.
> 
> 
> -------- Original-Nachricht --------
> Datum: Wed, 04 Apr 2007 15:29:55 +1000
> Von: Mark Andrews <Mark_Andrews at isc.org>
> An: Kal Feher <kal.feher at melbourneit.com.au>
> CC: bind-users at isc.org
> Betreff: Re: named listening on UDP
> 
> > 
> > 	This is also in the FAQ.
> > 
> > 	Q: Why is named listening on UDP port other than 53?
> > 
> > 	http://www.isc.org/sw/bind/FAQ.php
> >    
> > -- 
> > Mark Andrews, ISC
> > 1 Seymour St., Dundas Valley, NSW 2117, Australia
> > PHONE: +61 2 9871 4742                 INTERNET: Mark_Andrews at isc.org
> > 
> 
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> 
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: Mark_Andrews at isc.org