The Network Information Service or NIS is Sun Microsystems' "Yellow Pages" (YP) client-server directory service protocol for distributing system configuration data such as user and host names between computers on a computer network.
When students try to login using GNOME or KDE desktop graphical login manager it dump back error:
Cannot load user preferences from /home/username
User home directory is on NFS server and it will be mounted only after login procedure. NIS based automount works under text based login. But, when it comes to graphical login; it will dump back above error.
To fix this error you need to edit /etc/nsswitch.conf file and force automount to use NIS database:
# vi /etc/nsswitch.conf
Set automount as follows:
automount: nis files
Now Linux graphical login manager will accept logins without any error.