Name

named — Internet domain name server

Synopsis

named [-4] [-6] [-c config-file] [-d debug-level] [-f] [-g] [-n #cpus] [-p port] [-s] [-t directory] [-u user] [-v] [-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.

-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.

-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.

-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() 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() 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().

-v

Report the version number 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.

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.

FILES

/etc/named.conf

The default configuration file.

/var/run/named.pid

The default process-id file.

SEE ALSO

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

AUTHOR

Internet Systems Consortium