Login Access Restrictions

When a user logs in to a system, the login command consults the appropriate database according to the information that is listed in the /etc/nsswitch.conf file. The entries in this file can include files (which designates the /etc files), nis (which designates the NIS database), ldap (which designates the LDAP directory service), and nisplus (which designates the NIS+ database). For a description of this file, see the nsswitch.conf(4) man page. For information about naming or directory services, see System Administration Guide: Naming and Directory Services (DNS, NIS, and LDAP) or System Administration Guide: Naming and Directory Services (FNS and NIS+).

The login command verifies the user name and password that were entered. If the user name is not in the password file or the password is not correct for the user name, the login command denies access to the system. When the user supplies a user name from the password file and the correct password for the user name, the system grants the user access to the system.