What Is Network Information Service (NIS)?

In the early days of networking, Unix systems were administered using a centralized database that tracked all the users and files on each server. This database was called Network Information Service (NIS). Once computers got more powerful, it became clear that this method needed more scalable. You couldn't just have one database with all the information for every computer in your network; you had to have many. If one broke down, you had to manually fix it on each computer, a tedious process that could take hours or even days. So Sun Microsystems developed its version of NIS called Sun-NIS (Network Information System). It allowed administrators to manage their Unix systems from any location in the network via remote login sessions and maintain consistency across all machines within the same domain. The NIS server is the brains of the operation. It stores a central database of all your network's configuration data and serves it to clients when needed. The client machines are just what they sound like: they receive information from the NIS server. They don't store any info but can retrieve and use it when needed. Finally, there's you! As an administrator, you can set up your client machines with as little or as much configuration data as you need, then make changes from one central location. A network information service is like a cottage with a big, beautiful garden. The house is the server, and the park is the database. The server is a central repository for host configuration information. It has a master copy of that information, while secondary servers mirror this information for redundancy. The servers are shared, and clients depend on them for information. The host files, master password and groups are transmitted through the network information service. The client queries the NIS server when it requires information found in the local files.