Commands Reference, Volume 4

named8 Daemon

Purpose

Provides the server function for the Domain Name Protocol.

Syntax

/usr/sbin/named8 [ -d DebugLevel ] [ -p PortNumber ] [ -c ConfFile ] [ -w WorkingDirectory ] [ -t RootDirectory ] [ -q ] [ -r ] [ -f ]

Description

The /usr/sbin/named8 daemon is the server for the Domain Name Protocol (DOMAIN). The named8 daemon runs on name server hosts and controls the domain-name resolution function.

This operating system provides two name server daemons, the named4 daemon and the named8 daemon. While both provide the same service of domain-name resolution, the named8 daemon supports the more robust configuration file named.conf. The named8 daemon is also more current, supporting newer specifications, and containing many security fixes. The named4 daemon is being phased out of service in support of the named8 daemon, and as a result, users are encouraged to migrate their name server installations to the newer configuration format.

Selection of which name server daemon to use is controlled by the /usr/sbin/named and /usr/sbin/named-xfer symbolic links. By default, these are links to the named4 and named4-xfer executables, but can be changed to reference the named8 and named8-xfer executables. Note that it is required that both symbolic links are changed in tandem, as the version 4 name server is not compatible with the version 8 zone transfer, and vice-versa.

Note: The named8 daemon can be controlled using the System Resource Controller (SRC) or the System Management Interface Tool (SMIT). Use the rc.tcpip file to start the daemon with each system startup.

The named8 daemon listens for name-server requests generated by resolver routines running on foreign hosts. The daemon listens to the socket defined in the /etc/services file; the entry in the /etc/services file begins with domain. However, this socket assignment can be overridden using the -p flag on the command line.

Note: The /etc/resolv.conf file tells the local kernel and resolver routines to use the DOMAIN protocol. The /etc/resolv.conf file must exist and contain either the local host's address or the loopback address (127.0.0.1) to use the named8 daemon on the DOMAIN name server host. If the /etc/resolv.conf file does not exist, the local kernel and resolver routines use the /etc/hosts database. When this occurs, the named8 daemon does not function properly.

Manipulating the named8 Daemon with the System Resource Controller

The named8 daemon is a subsystem controlled by the System Resource Controller (SRC). The named8 daemon is a member of the tcpip system group. This daemon is disabled by default and can be manipulated by the following SRC commands:

startsrc	Starts a subsystem, group of subsystems,or a subserver.
stopsrc	Stops a subsystem, group of subsystems, or a subserver.
refresh	Causes the named8 daemon to reread the /etc/named.conf file. Depending on the contents of the file, the refresh command may or may not reload the listed databases.
traceson	Enables tracing of a subsystem, group of subsystems, or a subserver.
tracesoff	Disables tracing of a subsystem, group of subsystems, or a subserver.
lssrc	Gets the status of a subsystem, group of subsystems, or a subserver.

Flags

-b \| -cConfFile	Specifies an alternate configuration file.
-dDebugLevel	Provides a debugging option. The -d flag causes the named8 daemon to write debugging information to a file named by default /var/tmp/named.run. The DebugLevel variable determines the level of messages printed, with valid levels from 1 to 11, where level 11 supplies the most information.
-pPortNumber	Reassigns the Internet socket where the named8 daemon listens for DOMAIN requests. If this variable is not specified, the named8 daemon listens to the socket defined in the /etc/services file; the entry in the /etc/services file begins with `domain`.
-wWorkingDirectory	Changes the working directory of the named8 daemon. This option can be specified or overridden by the "directory" configuration option.
-tRootDirectory	Specifies a directory to be the new root directory for the named8 daemon using the chroot command.
-q	Enables logging of all name service queries.
-r	Disables the server's ability to recurse and resolve queries outside of the server's local databases.
-f	Indicates to run the name server daemon in the foreground rather than becoming a background job.

Signals

The following signals have the specified effect when sent to the named8 daemon process using the kill command:

SIGHUP	The named8 daemon rereads the /etc/named.conffile. Depending on the contents of the file, the SIGHUP signal may or may not reload the listed databases.
SIGILL	Dumps statistics data into named.stats. Statistics data is appended to the file.
SIGINT	The named8 daemon dumps the current database to a file named /var/tmp/named_dump.db. In the dump file, names with the label name error indicate negative cache entries. This happens when a server responds that the specified domain name does not exist. Names labeled as data error also indicate negative cache entries. This happens when a server responds that there are no records of the specified type for the (valid) domain name.
SIGUSR1	The named8 daemon turns on debugging; each subsequent SIGUSR1 signal increments the debugging level. The debugging information is written to the /var/tmp/named.run file.
SIGUSR2	The named8 daemon turns off debugging.

Examples

To start the named8 daemon normally, enter the following:
```
startsrc -s named
```
This command starts the daemon. You can use this command in the rc.tcpip file or on the command line. The -s flag specifies that the subsystem that follows is to be started. The process ID of the named8 daemon is stored in the /etc/named.pid file upon startup.
To stop the named8 daemon normally, enter:
```
stopsrc -s named
```
This command stops the daemon. The -s flag specifies that the subsystem that follows is to be stopped.
To get short status from the named8 daemon, enter:
```
lssrc -s named
```
This command returns the name of the daemon, the process ID of the daemon, and the state of the daemon (active or inactive).
To enable debugging for the named8 daemon, enter:
```
traceson -s named
```
OR
```
kill -30 `cat /etc/named.pid`
```
The named8 daemon turns on debugging in response to either of these commands; each subsequent command increments the debugging level. The debugging information is written to the /var/tmp/named.run file.
To turn off debugging for the named8 daemon, enter:
```
tracesoff
```
OR
```
kill -35 `cat /etc/named.pid`
```
Either of these commands immediately turns off all debugging.
To start the named8 daemon at the highest debugging level using the startsrc command, enter the following:
```
startsrc -s named -a -d11
```
This command writes debugging messages to the /var/tmp/named.run file.

Files

/usr/sbin/named8	Contains the named8 daemon.
/usr/sbin/named8-xfer	Provides the functionality of the slave name server's inbound zone transfer.
/etc/named.conf	Specifies the configuration of the named8 daemon including some basic behaviors, logging options, and locations of the local databases.
/etc/resolv.conf	Specifies the use of domain name services.
/etc/rc.tcpip	Initializes daemons at each system restart.
/etc/named.pid	Stores process ID.
/etc/services	Defines socket service assignments.
/usr/samples/tcpip/named.conf	Contains the sample named.conf file with directions for its use.
/usr/samples/tcpip/named.data	Contains the sample DOMAIN data file with directions for its use.
/usr/samples/tcpip/hosts.awk	Contains the sample awk script for converting an /etc/hosts file to an /etc/named.data file. This file also contains directions for its use.
/usr/samples/tcpip/addrs.awk	Contains the sample awk script for converting an /etc/hosts file to an /etc/named.rev file. This file also contains directions for its use.

Related Information

The nslookup command, traceroute command, kill command, chroot command.

The named4 daemon.

The named.conf file format, DOMAIN Cache file format, DOMAIN Data file format, DOMAIN Reverse Data file format, DOMAIN Local Data file format, resolv.conf file format.

TCP/IP Name Resolution and TCP/IP Daemons in AIX 5L Version 5.1 System Management Guide: Communications and Networks.

Configuring Name Servers and Planning for DOMAIN Name Resolution in AIX 5L Version 5.1 System Management Guide: Communications and Networks.