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lwresd(8)

NAME

       lwresd - lightweight resolver daemon

SYNOPSIS

       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 ]

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 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
       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

       -C config-file
	      Use  config-file	as  the  configuration	file  instead  of  the
	      default, /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
	      stderr.

       -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.

	      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.

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

BIND9				 June 30, 2000			     LWRESD(8)

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