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NAMED(8)			     BIND9			      NAMED(8)

       named - Internet domain name server

       named [-4] [-6] [-c config-file] [-d debug-level] [-E engine-name] [-f]
	     [-g] [-m flag] [-n #cpus] [-p port] [-s] [-S #max-socks]
	     [-t directory] [-u user] [-v] [-V] [-x cache-file]

       named is a Domain Name System (DNS) server, part of the BIND 9
       distribution from ISC. For more information on the DNS, see RFCs 1033,
       1034, and 1035.

       When invoked without arguments, named will read the default
       configuration file /etc/named.conf, read any initial data, and listen
       for queries.

	   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.

       -c config-file
	   Use config-file as the configuration file instead of the default,
	   /etc/named.conf. To ensure that reloading the configuration file
	   continues to work after the server has changed its working
	   directory due to to a possible directory option in the
	   configuration file, config-file should be an absolute pathname.

       -d debug-level
	   Set the daemon's debug level to debug-level. Debugging traces from
	   named become more verbose as the debug level increases.

       -E engine-name
	   Use a crypto hardware (OpenSSL engine) for the crypto operations it
	   supports, for instance re-signing with private keys from a secure
	   key store. When compiled with PKCS#11 support engine-name defaults
	   to pkcs11, the empty name resets it to no engine.

	   Run the server in the foreground (i.e. do not daemonize).

	   Run the server in the foreground and force all logging to stderr.

       -m flag
	   Turn on memory usage debugging flags. Possible flags are usage,
	   trace, record, size, and mctx. These correspond to the
	   ISC_MEM_DEBUGXXXX flags described in <isc/mem.h>.

       -n #cpus
	   Create #cpus worker threads to take advantage of multiple CPUs. If
	   not specified, named 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 queries on port port. If not specified, the default is
	   port 53.

	   Write memory usage statistics to stdout on exit.
		  Note: This option is mainly of interest to BIND 9 developers
		  and may be removed or changed in a future release.

       -S #max-socks
	   Allow named to use up to #max-socks sockets.
		  Warning: This option should be unnecessary for the vast
		  majority of users. The use of this option could even be
		  harmful because the specified value may exceed the
		  limitation of the underlying system API. It is therefore set
		  only when the default configuration causes exhaustion of
		  file descriptors and the operational environment is known to
		  support the specified number of sockets. Note also that the
		  actual maximum number is normally a little fewer than the
		  specified value because named reserves some file descriptors
		  for its internal use.

       -t directory
	   Chroot to directory after processing the command line arguments,
	   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(2) 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.
		  Note: On Linux, named uses the kernel's capability mechanism
		  to drop all root privileges except the ability to bind(2) to
		  a privileged port and set process resource limits.
		  Unfortunately, this means that the -u option only works when
		  named is run on kernel 2.2.18 or later, or kernel
		  2.3.99-pre3 or later, since previous kernels did not allow
		  privileges to be retained after setuid(2).

	   Report the version number and exit.

	   Report the version number and build options, and exit.

       -x cache-file
	   Load data from cache-file into the cache of the default view.
		  Warning: This option must not be used. It is only of
		  interest to BIND 9 developers and may be removed or changed
		  in a future release.

       In routine operation, signals should not be used to control the
       nameserver; rndc should be used instead.

	   Force a reload of the server.

	   Shut down the server.

       The result of sending any other signals to the server is undefined.

       The named configuration file is too complex to describe in detail here.
       A complete description is provided in the BIND 9 Administrator
       Reference Manual.

       named inherits the umask (file creation mode mask) from the parent
       process. If files created by named, such as journal files, need to have
       custom permissions, the umask should be set explicitly in the script
       used to start the named process.

	   The default configuration file.

	   The default process-id file.

       Red Hat SELinux BIND Security Profile:

       By default, Red Hat ships BIND with the most secure SELinux policy that
       will not prevent normal BIND operation and will prevent exploitation of
       all known BIND security vulnerabilities . See the selinux(8) man page
       for information about SElinux.

       It is not necessary to run named in a chroot environment if the Red Hat
       SELinux policy for named is enabled. When enabled, this policy is far
       more secure than a chroot environment. Users are recommended to enable
       SELinux and remove the bind-chroot package.

       With this extra security comes some restrictions:

       By default, the SELinux policy does not allow named to write any master
       zone database files. Only the root user may create files in the
       $ROOTDIR/var/named zone database file directory (the options {
       "directory" } option), where $ROOTDIR is set in /etc/sysconfig/named.

       The "named" group must be granted read privelege to these files in
       order for named to be enabled to read them.

       Any file created in the zone database file directory is automatically
       assigned the SELinux file context named_zone_t .

       By default, SELinux prevents any role from modifying named_zone_t
       files; this means that files in the zone database directory cannot be
       modified by dynamic DNS (DDNS) updates or zone transfers.

       The Red Hat BIND distribution and SELinux policy creates three
       directories where named is allowed to create and modify files:
       /var/named/slaves, /var/named/dynamic /var/named/data. By placing files
       you want named to modify, such as slave or DDNS updateable zone files
       and database / statistics dump files in these directories, named will
       work normally and no further operator action is required. Files in
       these directories are automatically assigned the 'named_cache_t' file
       context, which SELinux allows named to write.

       Red Hat BIND SDB support:

       Red Hat ships named with compiled in Simplified Database Backend
       modules that ISC provides in the "contrib/sdb" directory. Install bind-
       sdb package if you want use them

       The SDB modules for LDAP, PostGreSQL, DirDB and SQLite are compiled
       into named-sdb.

       See the documentation for the various SDB modules in
       /usr/share/doc/bind-sdb-*/ .

       RFC 1033, RFC 1034, RFC 1035, named-checkconf(8), named-checkzone(8),
       rndc(8), lwresd(8), named.conf(5), BIND 9 Administrator Reference

       Internet Systems Consortium

       Copyright (C) 2004-2009 Internet Systems Consortium, Inc. ("ISC")
       Copyright (C) 2000, 2001, 2003 Internet Software Consortium.

BIND9				 May 21, 2009			      NAMED(8)