lwresd.html revision 6ea1b817e31b89a627e146fe69e23ea0a64c89ec
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - Copyright (C) 2000, 2001 Internet Software Consortium.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - Permission to use, copy, modify, and distribute this software for any
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - purpose with or without fee is hereby granted, provided that the above
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - copyright notice and this permission notice appear in all copies.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT,
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley - WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>lwresd</TITLE
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyNAME="GENERATOR"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCONTENT="Modular DocBook HTML Stylesheet Version 1.63
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6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyALINK="#0000FF"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="APPLICATION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>lwresd</SPAN
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFNAMEDIV"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="APPLICATION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>lwresd</SPAN
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> -- lightweight resolver daemon</DIV
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFSYNOPSISDIV"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>Synopsis</H2
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>config-file</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>debug-level</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>directory</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFSECT1"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>DESCRIPTION</H2
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> is the daemon providing name lookup
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley services to clients that use the BIND 9 lightweight resolver
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley library. It is essentially a stripped-down, caching-only name
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley server that answers queries using the BIND 9 lightweight
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley resolver protocol rather than the DNS protocol.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> listens for resolver queries on a
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley UDP port on the IPv4 loopback interface, 127.0.0.1. This
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley means that <B
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> can only be used by
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley processes running on the local machine. By default UDP port
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley number 921 is used for lightweight resolver requests and
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Incoming lightweight resolver requests are decoded by the
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley server which then resolves them using the DNS protocol. When
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley the DNS lookup completes, <B
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley the answers in the lightweight resolver format and returns
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley them to the client that made the request.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FILENAME"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> contains any
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>nameserver</TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> entries, <B
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley sends recursive DNS queries to those servers. This is similar
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley to the use of forwarders in a caching name server. If no
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>nameserver</TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> entries are present, or if
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley forwarding fails, <B
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> resolves the
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley queries autonomously starting at the root name servers, using
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley a built-in list of root server hints.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFSECT1"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="VARIABLELIST"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>config-file</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>config-file</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley configuration file instead of the default,
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FILENAME"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>debug-level</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Set the daemon's debug level to <TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>debug-level</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley Debugging traces from <B
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley more verbose as the debug level increases.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Run the server in the foreground (i.e. do not daemonize).
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Run the server in the foreground and force all logging
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FILENAME"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> worker threads
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley to take advantage of multiple CPUs. If not specified,
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="COMMAND"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> will try to determine the
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley number of CPUs present and create one thread per CPU.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley If it is unable to determine the number of CPUs, a
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley single worker thread will be created.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Listen for lightweight resolver queries on port
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley not specified, the default is port 921.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Send DNS lookups to port <TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley specified, the default is port 53. This provides a
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley way of testing the lightweight resolver daemon with a
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley name server that listens for queries on a non-standard
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley port number.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Write memory usage statistics to <TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FILENAME"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> This option is mainly of interest to BIND 9 developers
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley and may be removed or changed in a future release.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley></BLOCKQUOTE
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>directory</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FUNCTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>chroot()</TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>directory</I
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley processing the command line arguments, but before
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley reading the configuration file.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="WARNING"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="WARNING"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyALIGN="CENTER"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> This option should be used in conjunction with the
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="OPTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> option, as chrooting a process
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley running as root doesn't enhance security on most
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley systems; the way <TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FUNCTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>chroot()</TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley defined allows a process with root privileges to
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley escape a chroot jail.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FUNCTION"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>setuid()</TT
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REPLACEABLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> after completing
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley privileged operations, such as creating sockets that
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley listen on privileged ports.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Report the version number and exit.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFSECT1"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyNAME="AEN137"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="VARIABLELIST"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FILENAME"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> The default configuration file.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="FILENAME"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> The default process-id file.
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFSECT1"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyNAME="AEN150"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>SEE ALSO</H2
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="CITEREFENTRY"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFENTRYTITLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="CITEREFENTRY"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFENTRYTITLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="CITEREFENTRY"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFENTRYTITLE"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley>resolver</SPAN
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyCLASS="REFSECT1"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob HalleyNAME="AEN162"
6ea1b817e31b89a627e146fe69e23ea0a64c89ecBob Halley> Internet Software Consortium