lwresd(1M)                                                       lwresd(1M)




 NAME    [Toc]    [Back]
      lwresd - lightweight resolver daemon

 SYNOPSIS    [Toc]    [Back]
      lwresd [-C config-file] [-d debuglevel] [-fgs] [-i pid-file] [-n #cpus]
           [-P query-port#] [-p port#] [-t directory] [-u user-id]

 DESCRIPTION    [Toc]    [Back]
      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 lwresd which
      then resolves them using the DNS protocol.  When the DNS lookup
      completes, lwresd encodes the answers from the name servers in the
      lightweight resolver format and returns them to the client that made
      the original 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 compiled-in
      list of root servers hints.

    Options    [Toc]    [Back]
           -C config-file
                     This option is used to use config-file as the
                     configuration file instead of the default,
                     /etc/resolv.conf.

           -d debuglevel
                     This option is used to set the daemon's debug level to
                     debuglevel.  Debugging traces from lwresd become more
                     verbose as the debug level increases.

           -f        This option is used to run lwresd in the foreground.

           -g        This option is used to run lwresd in the foreground and
                     force all logging to stderr.

           -i pid-file
                     This option is used to write the daemon's process id to
                     pid-file instead of the default pathname.




 Hewlett-Packard Company            - 1 -   HP-UX 11i Version 2: August 2003






 lwresd(1M)                                                       lwresd(1M)




           -n #cpus  This option is used to create #cpus worker threads to
                     take advantage of multiple CPUs.  If no option is
                     given, lwresd will try to determine the number of CPUs
                     present and create one thread per CPU. If lwresd is
                     unable to determine the number of CPUs, a single worker
                     thread is created.

           -P query-port#
                     This option is used to send DNS lookups to port number
                     query-port# when querying name servers.  This provides
                     a way of testing the lightweight resolver daemon with a
                     name server that listens for queries on a non-standard
                     port number.

           -p port#  This option is used to listen for lightweight resolver
                     queries on the loopback interface using UDP port port#
                     instead of the default port number, 921.

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

           -t directory
                     This option tells lwresd to chroot() to directory
                     immediately after reading its configuration file.

           -u user-id
                     This option is used to run lwresd as user-id, which is
                     a user name or numeric id that must be present in the
                     password file.  The lightweight resolver daemon will
                     change its user-id after it has carried out any
                     privileged operations, such as writing the process-id
                     file or binding a socket to a privileged port
                     (typically any port less than 1024).

    Notes    [Toc]    [Back]
      lwresd is a daemon for lightweight resolvers, not a lightweight daemon
      for resolvers.

 FILES    [Toc]    [Back]
           /etc/lwresd.conf              Default configuration file

           /var/run/lwresd.pid           Default process-id file

 SEE ALSO    [Toc]    [Back]
      named(1M).


 Hewlett-Packard Company            - 2 -   HP-UX 11i Version 2: August 2003