named(1M) System Administration Commands named(1M)NAME
named, in.named - Internet domain name server
SYNOPSISnamed [-fgsVv] [-c config-file] [-d debug-level] [-m flag]
[-n #cpus] [-p port] [-S #max-socks] [-t directory]
[-u user] [-x cache-file] [-4 | -6]
DESCRIPTION
The named utility 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 reads the default configuration
file /etc/named.conf, reads any initial data, and listens for queries.
in.named is a link to named.
OPTIONS
The following options are supported:
-4
Use only IPv4 transport. By default, both IPv4 and IPv6 transports
can be used. Options -4 and -6 are mutually exclusive.
-6
Use only IPv6 transport. By default, both IPv4 and IPv6 transports
can be used. Options -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 direc‐
tory 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 (that is, do not run as a daemon).
-g
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, and 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 #max-socks
Allow named to use up to #max-socks sockets.
This option should be unnecessary for the vast majority of users.
The use of this option could even be harmful, because the specified
value might exceed the limitation of the underlying system API. It
therefore should be 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 smaller than the
specified value because named reserves some file descriptors for
its internal use.
-s
Write memory usage statistics to stdout on exit.
This option is mainly of interest to BIND 9 developers and might be
removed or changed in a future release.
-t directory
Change the root directory using chroot(2) to directory after pro‐
cessing the command line arguments, but before reading the configu‐
ration file.
This option should be used in conjunction with the -u option, as
chrooting a process running as root does not enhance security on
most systems; the way chroot() is defined allows a process with
root privileges to escape a chroot jail.
-u user
Set the real user ID using setuid(2) to user after completing priv‐
ileged operations, such as creating sockets that listen on privi‐
leged ports.
-V
Report the version number and build options, and exit.
-v
Report the version number and exit.
-x cache-file
Load data from cache-file into the cache of the default view.
Do not use this option. It is of interest only to BIND 9 developers
and might be removed or changed in a future release.
EXTENDED DESCRIPTION
This section describes additional attributes of named.
SMF Properties
When starting named from the service management facility, smf(5), named
configuration is read from the service configuration repository. Use
svcprop(1) to list the properties and svccfg(1M) to make changes.
The following application configuration properties are available to
administrators:
options/server
Specifies the server executable to be used instead of the default
server, /usr/sbin/named.
options/configuration_file
Specifies the configuration file to be used instead of the default,
/etc/named.conf. A directory option might be specified in the con‐
figuration file. To ensure that reloading the configuration file
continues to work in such a situation, configuration_file should be
specified as an absolute pathname. This pathname should not include
the chroot_dir pathname. This property is the equivalent of the -c
option.
options/ip_interfaces
Specifies over which IP transport, IPv4 or IPv6, BIND will trans‐
mit. Possible values are IPv4 or IPv6. Any other setting assumes
all, the default. This property is the equivalent of command line
option -4 or -6
options/listen_on_port
Specifies the default UDP and TCP port to be used for listening to
DNS requests. This property is the equivalent of the command line
option -p port.
options/debug_level
Specifies the default debug level. The default is 0, which means no
debugging. The higher the number the more verbose debug information
becomes. Equivalent of the command line option -d debug_level.
options/threads
Specifies the number of CPU worker threads to create. The default
of 0 causes named to try and determine the number of CPUs present
and create one thread per CPU. Equivalent of command line option -n
#cpus.
options/chroot_dir
Specifies the directory to be used as the root directory after pro‐
cessing SMF properties and the command line arguments but before
reading the configuration file. Use this property when using a
chroot(2) environment. Synonymous to command line option -t path‐
name.
When using chroot(2), named is unable to disable itself when
receiving rndc(1M) stop or halt commands. Instead, you must use the
svcadm(1M) disable command.
In the event of a configuration error originating in one of the above
SMF application options, named displays a message providing information
about the error and the parameters that need correcting. The process
then exits with exit code SMF_EXIT_ERR_CONFIG.
At startup, in the event of an error other than a configuration error,
named exits with exit code SMF_EXIT_ERR_FATAL. Both of this code and
SMF_EXIT_ERR_CONFIG cause the start method, smf_method(5), to place the
service in the maintenance state, which can be observed with the
svcs(1) command svcs -x.
In addition to the properties listed above, the following property can
be used to invoke named as a user other than root:
start/user
Specifies the identity of the user that is invoking named. See
smf_method(5) and chroot(2). Note that the user must have
solaris.smf.manage.bind authorization. Without this role the named
will be unable to manage its SMF FMRI and named will automatically
be restarted by the SMF after an rndc(1M) stop or halt command. See
EXAMPLES for a sequence of commands that establishes the correct
authorization.
SIGNALS
In routine operation, signals should not be used to control the name‐
server; rndc(1M) 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 list of configuration options is provided in the named.conf man page
shipped with the BIND 9 distribution. A complete description is pro‐
vided in the BIND 9 Administrator Reference Manual.
EXAMPLES
Example 1 Configuring named to Transmit Only over IPv4 Networks
The following command sequence configures named such that it will
transmit only over IPv4 networks.
# svccfg -s svc:network/dns/server:default setprop \
> options/ip_interfaces=IPv4
# svcadm refresh svc:network/dns/server:default
#
Example 2 Listing Current Configuration File and Setting an Alternative
File
The following sequence of commands lists the current named configura‐
tion file and sets an alternative file.
# svcprop -p options/configuration_file dns/server:default
/etc/named.conf
# svccfg -s dns/server:default setprop \
> options/configuration_file=/var/named/named.conf
# svcadm refresh dns/server:default
# svcprop -p options/configuration_file dns/server:default
/var/named/named.conf
Example 3 Establishing Appropriate Authorization for named
To have named start with the solaris.smf.manage.bind authorization,
perform the steps shown below.
Add the user dnsadmin to the solaris.smf.manage.bind role:
# usermod -A solaris.smf.manage.bind dnsadmin
Observe effect of command:
# tail -1 /etc/user_attr
dnsadmin::::type=normal;auths=solaris.smf.manage.bind
Modify the service properties:
# svccfg
svc:> select svc:/network/dns/server:default
svc:/network/dns/server:default> setprop start/user = dnsadmin
svc:/network/dns/server:default> setprop start/group = dnsadmin
svc:/network/dns/server:default> exit
# svcadm refresh svc:/network/dns/server:default
# svcadm restart svc:/network/dns/server:default
Because only root has write access to create the default process-ID
file, /var/run/named/named.pid, named must be configured to use an
alternative path for the user dnsadmin. Here is an example of how to
accomplish this:
# mkdir /var/named/tmp
# chown dnsadmin /var/named/tmp
Shown below is what you must add to named.conf to make use of the
directory created above.
# head /etc/named.conf
options {
directory "/var/named";
pid-file "/var/named/tmp/named.pid";
};
FILES
/etc/named.conf
default configuration file
/var/run/named/named.pid
default process-ID file
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌─────────────────────────────┬─────────────────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├─────────────────────────────┼─────────────────────────────┤
│Availability │service/network/dns/bind │
├─────────────────────────────┼─────────────────────────────┤
│Interface Stability │Volatile │
└─────────────────────────────┴─────────────────────────────┘
SEE ALSOsvcs(1), named-checkconf(1M), named-checkzone(1M), rndc(1M), rndc-conf‐
gen(1M), svcadm(1M), svccfg(1M), svcprop(1), chroot(2), setuid(2),
bind(3SOCKET), attributes(5), smf(5), smf_method(5)
RFC 1033, RFC 1034, RFC 1035
See the BIND 9 Administrator's Reference Manual. As of the date of pub‐
lication of this man page, this document is available at
https://www.isc.org/software/bind/documentation.
The named.conf man page shipped with the BIND 9 distribution
SunOS 5.11 11 Jan 2010 named(1M)