In this example, a computer named oak makes its /apps/bin directory available to clients on the network (pine, maple, and spruce) by adding an entry to the /etc/exports file. The client com- puter (pine) sees that the resource is available and mounts the resource on its local file system at the mount point /oak/apps , after which any files, directories, or subdirectories from /apps/bin on oak are available to users on pine (given proper permissions).

Although it is often used as a file server (or other type of server), Linux is a general-purpose oper- ating system, so any Linux system can share file systems (export) as a server or use another com- puter's file systems (mount) as a client. Contrast this with dedicated file servers, such as NetWare, which can only share files with client computers (such as Windows workstations) and never act as a client.

NOTE
A file system is usually a structure of files and directories that exists on a single device (such as a hard disk partition or CD-ROM). A Linux file system refers to the entire direc- tory structure (which may include file systems from several disks or NFS resources), beginning from root (/) on a single computer. A shared directory in NFS may represent all or part of a computer's file system, which can be attached (from the shared directory down the directory tree) to another com- puter's file system.

Getting NFS

While nearly every Linux system supports NFS client and server features, NFS is not always installed by default. You'll need different packages for different Linux systems to install NFS. Here are some examples:
Fedora and other Red Hat Linux systems - You need to install the nfs-utils package to use Fedora as an NFS server. There is also a graphical NFS Configuration tool that requires you to install the system-config-nfs package. NFS client features are in the base operating system. To turn on the nfs service, type the following:
# service nfs start
# chkconfig nfs on