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$Id: named.8,v 1.12 2001/01/09 21:47:16 bwelling Exp $
.Dd Jun 30, 2000 .Dt NAMED 8 .Os BIND9 9 .Sh NAME .Nm named .Nd Internet domain name server .Sh SYNOPSIS .Nm named .Op Fl c Ar config-file .Op Fl d Ar debuglevel .Op Fl f g s .Op Fl n Ar #cpus .Op Fl p Ar port# .Op Fl t Ar directory .Op Fl u Ar user-id .Op Fl v .Op Fl x Ar cache-file .Sh DESCRIPTION .Nm 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.

p When invoked without arguments, .Nm named will read the default configuration file

a /etc/named.conf , read any initial data, and listen for queries.

p The options to .Nm named are as follows: l -tag -width Ds t Fl c use .Ar config-file as the configuration file instead of the default,

a /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 .Dv directory option in the configuration file, .Ar config-file should be an absolute pathname. t Fl d set the daemon's debug level to .Ar debuglevel . Debugging traces from .Nm named become more verbose as the debug level increases. t Fl f run .Nm named in the foreground. t Fl g run .Nm named in the foreground and force all logging to .Dv stderr . t Fl n create .Ar #cpus worker threads to take advantage of multiple CPUs. If no option is given, .Nm named will try to determine the number of CPUs present and create one thread per CPU. If .Nm named is unable to determine the number of CPUs, a single worker thread is created. t Fl p listen for queries on port .Ar port# instead of the default port number, 53. t Fl s write memory usage statistics to .Dv stdout on exit. This option is mainly of interest to BIND9 developers and may be removed or changed in a future release. t Fl t tells .Nm named to chroot() to .Ar directory immediately after reading its config file. This should be used in conjunction with the .Fl 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 the chroot jail. t Fl u run .Nm named as UID .Ar user-id . .Nm named will change its UID after it has carried out any privileged operations, such as creating sockets that listen on privileged ports.

p On Linux, .Nm named uses the kernel's capability mechanism to drop all root privileges except the ability to bind() to a privileged port. Unfortunately, this means that the "-u" option only works when .Nm named is run on 2.3.99-pre3 or later kernel, since previous kernels did not allow privileges to be retained after setuid(). t Fl v report the version number and exit. t Fl x load data from .Ar cache-file . into the cache of the default view. This option must not be used. It is only of interest to BIND9 developers and may be removed or changed in a future release. .El .Sh SIGNALS In routine operation, signals should not be used to \*qcontrol\*q the name server. .Nm rndc should be used instead. Sending the name server a .Dv SIGHUP signal forces a reload of the server. A .Dv SIGINT or .Dv SIGTERM signal can be used to gracefully shut down the server. Sending any other signals to the name server will have an undefined outcome. .Sh CONFIGURATION FILE FORMAT
.Nm named 's
configuration file is too complex to describe in detail here.
A complete description is provided in the BIND9 Administrator
Reference Manual.
.Sh FILES l -tag -width /var/run/named.pid -compact t Pa /etc/named.conf default configuration file t Pa /var/run/named.pid default process-id file .El .Sh SEE ALSO .Xr RFC1033 , .Xr RFC1034 , .Xr RFC1035 , .Xr rndc 8 , .Xr lwresd 8 , BIND9 Administrator Reference Manual, June 2000.