An NIS system maintains and distributes a central directory of user and group information, hostnames, e-mail aliases and other text-based information in a network.

Though not the core purpose, NIS can be used for centralized authentication too.

Server packages:

ypserve
ypbind
make

Client package:

ypbind

Procedure to create an NIS authentication server:

Logon to server host
Create users and assign password
Edit /etc/sysconfig/network and add the line “NISDOMAIN=llc”
Start the ypserv service
Create a database for the master NIS servers
# /usr/lib/yp/ypinit -m
If this is the only server press “Q”
A new folder /var/yp/llc will be created.
Edit /etc/hosts with the following entry
www.llc
In the client run the tool authconfig.
Enable NIC and give the servers IP address.
Logout and try loging back

Client host] # ypwhich : Shows the server to which the host is connected.

Client host] # ypcat password : Displays the password database

We might need to mount home directories from the server. Mounting it using autofs should be good.

NIS slave

It is good to run an NIS slave server in a network. By this, if the primary server goes down, the slave should be able to perform authentication. The slave replicated its database from the primary frequently.

Procedure to configure an NIS slave:

Append “NISDOMAIN=llc” in /etc/sysconfig/network
Start the service ypserv
Run the command /usr/lib/yp/ypinit -S
The database gets populated in /var/yp/llc automatically

If any change is done in an NIS server, the database should be recreated using
# make -c /var/yp