Managing NFS and NIS, 2nd Edition

Chapter 3. Network Information Service Operation

A major problem in running a distributed computing environment is maintaining separate copies of common configuration files such as the password, group, and hosts files. Ideally, the network should be consistent in its configuration, so that users don’t have to worry about where they have accounts or if they’ll be able to find a new machine on the network. Preserving consistency, however, means that every change to one of these common files must be propagated to every host on the network. In a small network, this might not be a major chore, but in a computing environment with hundreds or thousands of systems, simple administrative tasks can turn into all-day projects. Furthermore, without an automated tool for making changes, the probability of making mistakes grows with the size of the network and the number of places where changes must be made.

The Network Information System (NIS) addresses these problems. It is a distributed database system that replaces copies of commonly replicated configuration files with a centralized management facility. Instead of having to manage each host’s files (like /etc/hosts, /etc/passwd, /etc/group, /etc/ethers, and so on), you maintain one database for each file on one central server. Machines that are using NIS retrieve information as needed from these databases. If you add a new system to the network, you can modify one file on a central server and propagate this change to the rest of the network, ...