NAME
lwresd - lightweight resolver daemon
SYNOPSIS
llwwrreessdd [-cc config-file] [-CC config-file] [-dd debug-level] [-ff] [-gg]
[-ii pid-file] [-mm flag] [-nn #cpus] [-PP port] [-pp port] [-ss]
[-tt directory] [-uu user] [-vv] [-44] [-66]
DESCRIPTION
llwwrreessdd is the daemon providing name lookup services to clients that use the BIND 9 lightweight resolver library. It is essentially astripped-down, caching-only name server that answers queries using the
BIND 9 lightweight resolver protocol rather than the DNS protocol. llwwrreessdd listens for resolver queries on a UDP port on the IPv4 loopback interface, 127.0.0.1. This means that llwwrreessdd 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, llwwrreessdd encodes the answers in the lightweight resolver format and returns them to the client that made the request. If /etc/resolv.conf contains any nnaammeesseerrvveerr entries, llwwrreessdd sends recursive DNS queries to those servers. This is similar to the use of forwarders in a caching name server. If no nnaammeesseerrvveerr entries are present, or if forwarding fails, llwwrreessdd resolves the queriesautonomously starting at the root name servers, using a built-in list
of root server hints. OOPPTTIIOONNSS-4
Use IPv4 only even if the host machine is capable of IPv6. -44 and
-66 are mutually exclusive.
-6
Use IPv6 only even if the host machine is capable of IPv4. -44 and
-66 are mutually exclusive.
-c config-file
Use config-file as the configuration file instead of the default,
/etc/lwresd.conf. -cc can not be used with -CC.
-C config-file
Use config-file as the configuration file instead of the default,
/etc/resolv.conf. -CC can not be used with -cc.
-d debug-level
Set the daemon's debug level to debug-level. Debugging traces from
llwwrreessdd 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.-i pid-file
Use pid-file as the PID file instead of the default,
/var/run/lwresd.pid.
-m flag
Turn on memory usage debugging flags. Possible flags are usage, trace, and record. These correspond to the ISCMEMDEBUGXXXX flags described in. -n #cpus
Create #cpus worker threads to take advantage of multiple CPUs. If
not specified, llwwrreessdd 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.-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 anon-standard port number.
-s
Write memory usage statistics to stdout on exit. NNoottee:: This option is mainly of interest to BIND 9 developers and may be removed or changed in a future release.-t directory
CChhrroooott to directory after processing the command line arguments, but before reading the configuration file. WWaarrnniinngg:: This option should be used in conjunction with the-uu option, as chrooting a process running as root doesn't
enhance security on most systems; the way cchhrroooott((22)) is defined allows a process with root privileges to escape a chroot jail.-u user
SSeettuuiidd 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
nnaammeedd(8), llwwrreess(3), rreessoollvveerr(5). AUTHOR Internet Systems Consortium COPYRIGHT Copyright (C) 2004, 2005, 2007, 2008 Internet Systems Consortium, Inc. ("ISC") Copyright (C) 2000, 2001 Internet Software Consortium. BIND9 June 30, 2000 LWRESD(8)