NIS Client Configuration with authconfig

authconfig stands for "Authentication Configuration" and makes interfacing with the NIS system easy.
Once you are correctly communicating with the NIS system, you can use the network's preset information for usernames, passwords, hostnames, and other categories. To run authconfig, you must be logged in as root and type the full path,

/usr/sbin/authconfig

, unless

/usr/sbin

is in your PATH variable.

Authconfig is a command-line tool in Red Hat Linux that simplifies the configuration of various system authentication and identification services, including NIS (Network Information Service). Authconfig provides an easy way to configure the system to use NIS for user authentication and other system entities, by automating the process of modifying various configuration files.
When configuring NIS with authconfig, the tool modifies several files, including the /etc/nsswitch.conf file, which specifies the order in which various databases and services are consulted when looking up system entities. Authconfig adds the "nis" keyword to the appropriate lines in the file, indicating that NIS should be used as a source of information.
Authconfig also modifies the /etc/sysconfig/network file to specify the name of the NIS domain to use for authentication, as well as the /etc/yp.conf file to specify the NIS server hostname or IP address.
By using authconfig, the process of configuring NIS becomes much easier and less error-prone, as the tool handles all the necessary modifications to the configuration files. This can be especially useful in large-scale deployments where multiple systems need to be configured to use NIS.

authconfig gives you the option to use NIS password files instead of local password files. This allows you to keep the same login information across the network. When you use NIS, you must specify your NIS domain and how to reach the NIS server.
There are two ways to specify the NIS server. You can instruct the computer to ask all hosts (broadcast^[1]) on the subnet for NIS information. This method is not preferred because any computer that responds quickly enough will supply network information to your computer. A better way to configure each computer is with the IP address of the NIS server in use. Use the MouseOver below to browse through the options in authconfig.

authconfig Interface
The next lesson shows you how to use the command line to configure an NIS client.

[1] Broadcast: To send information to an IP address that all network hosts listen to. You can broadcast a message across an entire subnet.