Chapter 25. Authentication Configuration
When a user logs in to a Red Hat Enterprise Linux system, the username and password combination must be verified, or authenticated, as a valid and active user. Sometimes the information to verify the user is located on the local system, and other times the system defers the authentication to a user database on a remote system.
The Authentication Configuration Tool provides a graphical interface for configuring user information retrieval from NIS, LDAP, and Hesiod servers. This tool also allows you to configure LDAP, Kerberos, and SMB as authentication protocols.
If you configured a medium or high security level during installation (or with the Security Level Configuration Tool), then the firewall will prevent NIS (Network Information Service) authentication.
This chapter does not explain each of the different authentication types in detail. Instead, it explains how to use the Authentication Configuration Tool to configure them.
To start the graphical version of the Authentication Configuration Tool from the desktop, select the System (on the panel) => Administration => Authentication or type the command system-config-authentication at a shell prompt (for example, in an XTerm or a GNOME terminal).
After exiting the authentication program, the changes made take effect immediately.