Time Based Restrictions
These examples will limit the login times of certain users. See /etc/security/time.conf for more information/examples. In order to place time restrictions on user logins, the following must be placed in /etc/pam.d/login:

account    required    /lib/security/pam_time.so

The remaining lines should be placed in /etc/security/time.conf.

1. Only allow user nikesh to login