Download Building and Improving a Linux Cluster

all the accounts and passwords for each user. The files containing the account names, group
names, passwords and home directories of each user is then mounted to each computer
in the cluster using NIS. The NIS method allows for the administrator to create one user
account on the master, and mount it using NIS to the other nodes. This allows users to
access their information on every computer node, as well as use MPICH which requires that
type of consistency throughout the cluster.
The last authentication method is Lightweight Directory Access Protocol, or LDAP.
After the industry standard NIS was used for many years, a bug was found in the system.
Users could access the passwords folder on a cluster using NIS, by copying previous command history into a terminal window. This would allow anyone who is logging into the
computer (users, administrators, and hackers) to access any account and any file on the
machine. LDAP was created as the alternative to NIS. LDAP uses a Data Interchange File
(LDIF) to create and maintain user authentication. The LDIF file is shared throughout the
network and mounted similarly to NIS, but without sacrificing the security of the network.
The BYU-Idaho Cluster was designed so many students could access and use the cluster.
Each node in the cluster was designed to act as a single computer by itself as well. Because
of the large number of students who where anticipated to use the cluster, NIS authentication
was setup. Shortly after NIS was up and running, an error occurred and NIS is no longer
running properly. The Cluster currently runs regular authentication, however script files
have been written to help administrators setup and maintain the cluster status.
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