named - Internet domain name server
named [-4] [-6] [-c config-file] [-d debug-level] [-f] [-g]
[-i pid-file] [-m flag] [-n #cpus] [-p port] [-s] [-t directory]
[-u user] [-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 fork into two processes for
privilege separation, chroot(2) to /var/named, read the default
configuration file /var/named/etc/named.conf, read any initial data,
and listen for queries. The privileged process will communicate with
the child and bind(2) to privileged ports on its behalf. See CAVEATS
-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.
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
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
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>.
Specifies the file that contains the process ID of named. The
default is /var/run/named.pid.
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
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.
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.
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
-v Report the version number and exit.
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
In routine operation, signals should not be used to control the
nameserver; rndc should be used instead.
SIGHUP 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
named runs privilege separated for binding the privileged ports
after an interface or address change. The privileged process will only
allow named to bind(2) to default ports. Make sure you use unprivileged
(>1024) ports if you change any of the default ports in named's
configuration or on the command-line.
The default configuration file.
The default process-id file.
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
June 30, 2000 NAMED(8)
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