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LWRESD(8)							     LWRESD(8)

       lwresd -	lightweight resolver daemon

       lwresd  [  -C  config-file  ]  [	-d debug-level ]  [ -f ]  [ -g ]  [ -i
       pid-file	]  [ -n	#cpus ]	 [ -P port ]  [	-p port	]  [ -s	]  [ -t	direc-
       tory ]  [ -u user ]  [ -v ]

       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,  This means that lwresd can only be used by pro-
       cesses 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  com-
       pletes,	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  re-
       cursive	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 au-
       tonomously starting at the root name servers, using a built-in list  of
       root server hints.

       -C config-file
	      Use  config-file	as  the	 configuration file instead of the de-
	      fault, /etc/resolv.conf.

       -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

       -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

       -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 argu-
	      ments, 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() 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.

	      The default configuration	file.

	      The default process-id file.

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

       Internet	Systems	Consortium

BIND9				 June 30, 2000			     LWRESD(8)


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