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LWRESD(8)			     BIND9			     LWRESD(8)

NAME
       lwresd -	lightweight resolver daemon

SYNOPSIS
       lwresd [-c config-file] [-C config-file]	[-d debug-level] [-f] [-g]
	      [-i pid-file] [-m	flag] [-n #cpus] [-P port] [-p port] [-s]
	      [-t directory] [-u user] [-v] [-4] [-6]

DESCRIPTION
       lwresd is the daemon providing name lookup services to clients that use
       the BIND	9 lightweight resolver library.	It is essentially a
       stripped-down, caching-only name	server that answers queries using the
       BIND 9 lightweight resolver protocol rather than	the DNS	protocol.

       lwresd listens for resolver queries on a	UDP port on the	IPv4 loopback
       interface, 127.0.0.1. This means	that lwresd can	only be	used by
       processes running on the	local machine. By default, UDP port number 921
       is used for lightweight resolver	requests and responses.

       Incoming	lightweight resolver requests are decoded by the server	which
       then resolves them using	the DNS	protocol. When the DNS lookup
       completes, lwresd encodes the answers in	the lightweight	resolver
       format and returns them to the client that made the request.

       If /etc/resolv.conf contains any	nameserver entries, lwresd sends
       recursive DNS queries to	those servers. This is similar to the use of
       forwarders in a caching name server. If no nameserver entries are
       present,	or if forwarding fails,	lwresd resolves	the queries
       autonomously starting at	the root name servers, using a built-in	list
       of root server hints.

OPTIONS
       -4
	   Use IPv4 only even if the host machine is capable of	IPv6.  -4 and
	   -6 are mutually exclusive.

       -6
	   Use IPv6 only even if the host machine is capable of	IPv4.  -4 and
	   -6 are mutually exclusive.

       -c config-file
	   Use config-file as the configuration	file instead of	the default,
	   /etc/lwresd.conf.  -c can not be used with -C.

       -C config-file
	   Use config-file as the configuration	file instead of	the default,
	   /etc/resolv.conf.  -C can not be used with -c.

       -d debug-level
	   Set the daemon's debug level	to debug-level.	Debugging traces from
	   lwresd become more verbose as the debug level increases.

       -f
	   Run the server in the foreground (i.e. do not daemonize).

       -g
	   Run the server in the foreground and	force all logging to stderr.

       -i pid-file
	   Use pid-file	as the PID file	instead	of the default,
	   /var/run/lwresd/lwresd.pid.

       -m flag
	   Turn	on memory usage	debugging flags. Possible flags	are usage,
	   trace, record, size,	and mctx. These	correspond to the
	   ISC_MEM_DEBUGXXXX flags described in	_isc/mem.h_.

       -n #cpus
	   Create #cpus	worker threads to take advantage of multiple CPUs. If
	   not specified, lwresd will try to determine the number of CPUs
	   present and create one thread per CPU. If it	is unable to determine
	   the number of CPUs, a single	worker thread will be created.

       -P port
	   Listen for lightweight resolver queries on port port. If not
	   specified, the default is port 921.

       -p port
	   Send	DNS lookups to port port. If not specified, the	default	is
	   port	53. This provides a way	of testing the lightweight resolver
	   daemon with a name server that listens for queries on a
	   non-standard	port number.

       -s
	   Write memory	usage statistics to stdout on exit.
		  Note:	This option is mainly of interest to BIND 9 developers
		  and may be removed or	changed	in a future release.

       -t directory
	   Chroot to directory after processing	the command line arguments,
	   but before reading the configuration	file.
		  Warning: This	option should be used in conjunction with the
		  -u option, as	chrooting a process running as root doesn't
		  enhance security on most systems; the	way chroot(2) is
		  defined allows a process with	root privileges	to escape a
		  chroot jail.

       -u user
	   Setuid to user after	completing privileged operations, such as
	   creating sockets that listen	on privileged ports.

       -v
	   Report the version number and exit.

FILES
       /etc/resolv.conf
	   The default configuration file.

       /var/run/lwresd.pid
	   The default process-id file.

SEE ALSO
       named(8), lwres(3), resolver(5).

AUTHOR
       Internet	Systems	Consortium

COPYRIGHT
       Copyright (C) 2004, 2005, 2007-2009 Internet Systems Consortium,	Inc.
       ("ISC")
       Copyright (C) 2000, 2001	Internet Software Consortium.

BIND9				 June 30, 2000			     LWRESD(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | FILES | SEE ALSO | AUTHOR | COPYRIGHT

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