This section includes basic terminology that must be understood to work with the NFS service. For more information about the NFS service, see Commands for Managing Network File Systems.
IPv4 addresses used in this documentation are blocks 192.0.2.0/24, 198.51.100.0/24, and 203.0.113.0/24.
To show a subnet, the block is divided into multiple subnets by borrowing enough bits from the host to create the required subnet. For example, host address 192.0.2.0 might have subnets 192.0.2.32/27 and 192.0.2.64/27.
IPv6 addresses have prefix 2001:DB8::/32.
The terms client and server describe the roles that a system assumes when sharing file systems. Servers are systems that share their file systems over a network. The systems that access these file systems are the clients.
Clients access files on the server by mounting the server's shared file systems. When a client mounts a remote file system, the client does not make a copy of the file system. Rather, the mounting process uses a series of remote procedure calls that enable the client to access the server's shared file system transparently. The mount resembles a local mount. You can type commands as if the file systems are local. For more information, see Mounting File Systems.
After a file system has been shared on a server through an NFS operation, the file system can be accessed from a client. You can mount an NFS file system automatically with autofs. For information about autofs, see About Autofs. For information about tasks that involve the share command and autofs, see Automatic File System Sharing and Figure 6, Table 6, Tasks for Administering Autofs.
The objects that can be shared with the NFS service include any whole or partial directory tree or a file hierarchy, including a single file. A system cannot share a file hierarchy that overlaps a file hierarchy that is already shared. Peripheral devices such as modems and printers cannot be shared.
In most UNIX system environments, a file hierarchy that can be shared corresponds to a file system or to a portion of a file system. However, because NFS works across operating systems and the concept of a file system might be meaningless in non-UNIX environments, the term file system refers to a file or file hierarchy that can be shared and mounted with NFS.