NAME

       named - Internet domain name server

SYNOPSIS

       named [[-4] | [-6]] [-c config-file] [-d debug-level] [-D string] [-E engine-name] [-f] [-g] [-L logfile]
             [-M option] [-m flag] [-n #cpus] [-p port] [-s] [-S #max-socks] [-t directory] [-U #listeners]
             [-u user] [-v] [-V] [-X lock-file] [-x cache-file]

DESCRIPTION

       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.

OPTIONS

       -4
           Use IPv4 only even if the host machine is capable of IPv6.  -4 and -6 are mutually exclusive.

       -6
           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.

       -D string
           Specifies a string that is used to identify a instance of named in a process listing. The contents of
           string are not examined.

       -E engine-name
           When applicable, specifies the hardware to use for cryptographic operations, such as a secure key
           store used for signing.

           When BIND is built with OpenSSL PKCS#11 support, this defaults to the string "pkcs11", which
           identifies an OpenSSL engine that can drive a cryptographic accelerator or hardware service module.
           When BIND is built with native PKCS#11 cryptography (--enable-native-pkcs11), it defaults to the path
           of the PKCS#11 provider library specified via "--with-pkcs11".

       -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.

       -L logfile
           Log to the file logfile by default instead of the system log.

       -M option
           Sets the default memory context options. Currently the only supported option is external, which
           causes the internal memory manager to be bypassed in favor of system-provided memory allocation
           functions.

       -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.

       -s
           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. The default value is 4096 on systems built with default
           configuration options, and 21000 on systems built with "configure --with-tuning=large".

               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 #listeners
           Use #listeners worker threads to listen for incoming UDP packets on each address. If not specified,
           named will calculate a default value based on the number of detected CPUs: 1 for 1 CPU, and the
           number of detected CPUs minus one for machines with more than 1 CPU. This cannot be increased to a
           value higher than the number of CPUs. If -n has been set to a higher value than the number of
           detected CPUs, then -U may be increased as high as that value, but no higher. On Windows, the number
           of UDP listeners is hardwired to 1 and this option has no effect.

       -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).

       -v
           Report the version number and exit.

       -V
           Report the version number and build options, and exit.

       -X lock-file
           Acquire a lock on the specified file at runtime; this helps to prevent duplicate named instances from
           running simultaneously. Use of this option overrides the lock-file option in named.conf. If set to
           none, the lock file check is disabled.

       -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.

SIGNALS

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

       SIGHUP
           Force a reload of the server.

       SIGINT, SIGTERM
           Shut down the server.

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

CONFIGURATION

       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.

FILES

       /etc/named.conf
           The default configuration file.

       /var/run/named/named.pid
           The default process-id file.

SEE ALSO

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

AUTHOR

       Internet Systems Consortium, Inc.

COPYRIGHT

       Copyright © 2000, 2001, 2003-2009, 2011, 2013-2017 Internet Systems Consortium, Inc. ("ISC")

ISC                                                2014-02-19                                           NAMED(8)