In computing

Computing

Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...

, a NetWare File System (NWFS) is a file system

File system

A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...

 based on a heavily-modified version of FAT

File Allocation Table

File Allocation Table is a computer file system architecture now widely used on many computer systems and most memory cards, such as those used with digital cameras. FAT file systems are commonly found on floppy disks, flash memory cards, digital cameras, and many other portable devices because of...

. It was used in the Novell NetWare

Novell NetWare

NetWare is a network operating system developed by Novell, Inc. It initially used cooperative multitasking to run various services on a personal computer, with network protocols based on the archetypal Xerox Network Systems stack....

 operating system

Operating system

An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...

. It is the default and only file system for all volumes in versions 2.x through 4.x, and the default and only file system for the SYS volume continuing through version 5.x. Novell developed two varieties of NWFS:

1. 16-bit NWFS 286, used in NetWare 2.x
2. 32-bit NWFS 386, used in NetWare 3.x through NetWare 6.x.

Novell Storage Services

Novell Storage Services

Novell Storage Services is a file system used by the Novell NetWare operating system. Recently support of NSS was introduced to SUSE Linux via low-level network NCPFS protocol...

 (NSS, released in 1998), superseded the NWFS format.

The NWFS on-disk format was never publicly documented by Novell. The published specifications for 32-bit NWFS are:

• Maximum file size: 4GB
• Maximum volume size: 1TB
• Maximum files per volume: 2 million when using a single name space.
• Maximum files per server: 16 million
• Maximum directory entries: 16 million
• Maximum volumes per server: 64
• Maximum volumes per partition: 8
• Maximum open files per server: 100,000
• Maximum directory tree depth: 100 levels
• Characters used: ASCII double-byte
• Maximum extended attributes: 16
• Maximum data streams
  Fork (filesystem)
  In a computer file system, a fork is byte stream associated with a file system object. Every non-empty file must have at least one fork, and depending on the file system, a file may have one or more other associated forks, which in turn may contain primary data integral to the file, or just metadata...
  
  : 10
• Support for different name spaces: Microsoft
  Microsoft
  Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...
  
   Windows
  Microsoft Windows
  Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
  
   Long names
  Long filename
  Long filenames , are Microsoft's way of implementing filenames longer than the 8.3 filename, or short-filename, naming scheme used in Microsoft DOS in their modern FAT and NTFS filesystems. Because these filenames can be longer than an 8.3 filename, they can be more descriptive...
  
   (A.K.A. OS/2
  OS/2
  OS/2 is a computer operating system, initially created by Microsoft and IBM, then later developed by IBM exclusively. The name stands for "Operating System/2," because it was introduced as part of the same generation change release as IBM's "Personal System/2 " line of second-generation personal...
  
   namespace), Unix
  Unix
  Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
  
  , Apple
  Apple Computer
  Apple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...
  
   Macintosh
• Support for restoring deleted files (salvage)
• Support for journaling (transaction tracking service)
• Support for block suballocation, starting in NetWare 4.x

Transparent file compression was also supported, although this had a significant impact on the performance of file serving.

Every name space requires its own separate directory entry for each file. While the maximum number of directory entries is 16,000,000, two resident name spaces would reduce the usable maximum number of directory entries to 8,000,000, and three to 5,333,333.

16-bit NWFS could handle volumes of up to 256 MB. However, its only name-space support was a dedicated API

Application programming interface

An application programming interface is a source code based specification intended to be used as an interface by software components to communicate with each other...

 to handle Macintosh clients.

See also

• List of file systems
• Comparison of file systems
  Comparison of file systems
  -General information:-Limits:-Metadata:-Features:-Allocation and layout policies:-Supporting operating systems:-See also:* Comparison of archive formats* Comparison of file archivers* List of archive formats* List of file archivers...