lwresd — lightweight resolver daemon
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]
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.
    
	    Use IPv4 only even if the host machine is capable of IPv6.
	    -4 and -6 are mutually
	    exclusive.
	  
	    Use IPv6 only even if the host machine is capable of IPv4.
	    -4 and -6 are mutually
	    exclusive.
	  
config-file
	    Use config-file as the
	    configuration file instead of the default,
	    /etc/lwresd.conf.
	    <term>-c</term> can not be used with <term>-C</term>.
	  
config-file
	    Use config-file as the
	    configuration file instead of the default,
	    /etc/resolv.conf.
	    <term>-C</term> can not be used with <term>-c</term>.
	  
debug-level
		Set the daemon's debug level to debug-level.
		Debugging traces from lwresd become
		more verbose as the debug level increases.
	  
Run the server in the foreground (i.e. do not daemonize).
		Run the server in the foreground and force all logging
		to stderr.
	  
pid-file
	    Use pid-file as the
	    PID file instead of the default,
	    /var/run/lwresd.pid.
	  
flag
	    Turn on memory usage debugging flags.  Possible flags are
	    usage,
	    trace, and
	    record.
	    These correspond to the ISC_MEM_DEBUGXXXX flags described in
	    <isc/mem.h>.
	  
#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.
	  
port
		Listen for lightweight resolver queries on port
		port.  If
		not specified, the default is port 921.
	  
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.
	  
		Write memory usage statistics to stdout
		on exit.
	  
This option is mainly of interest to BIND 9 developers and may be removed or changed in a future release.
directory
		Chroot to directory after
		processing the command line arguments, but before
		reading the configuration file.
	  
		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.
	    
user
		Setuid to user after completing
		privileged operations, such as creating sockets that
		listen on privileged ports.
	  
Report the version number and exit.