A File System Defined
A file system is a collection of files and directories stored on disk in a standard Unix file system (UFS) format. All disk-based computer systems have a file system. In Unix, file systems have two basic components: files and directories. A file is the actual information as it is stored on the disk, and a directory is a list of the filenames. In addition to keeping track of filenames, the file system must keep track of files' access dates, permissions, and ownership. Managing file systems is one of the system administrator's most important tasks. Administration of the file system involves the following:
You'll see the term file system used in several ways. Usually, file system describes a particular type of file system (disk-based, network based, or virtual). It might also describe the entire file tree from the root directory downward. In another context, the term file system might be used to describe the structure of a disk slice, described later in this chapter.
The Solaris system software uses the virtual file system (VFS) architecture, which provides a standard interface for different file system types. The VFS architecture lets the kernel handle basic operations, such as reading, writing, and listing files, without requiring the user or program to know about the underlying file system type. Furthermore, Solaris provides file system administrative commands that enable you to maintain file systems.