filesystems(5)

NAME

filesystems - Linux file-system types: minix, ext, ext2, ext3, ext4, Reiserfs, XFS, JFS, xia, msdos, umsdos, vfat, ntfs, proc, nfs, iso9660, hpfs, sysv, smb, ncpfs

DESCRIPTION

When, as is customary, the proc file system is mounted on /proc, you can find in the file /proc/filesystems which file systems your kernel currently supports. If you need a currently unsupported one, insert the corresponding module or recompile the kernel.

In order to use a file system, you have to mount it; see mount(8).

Below a short description of a few of the available file systems.

minix is the file system used in the Minix operating system, the

first to run under Linux. It has a number of shortcomings: a 64MB partition size limit, short filenames, a single timestamp, etc. It remains useful for floppies and RAM disks.

ext is an elaborate extension of the minix file system. It has

been completely superseded by the second version of the extended file system (ext2) and has been removed from the kernel (in 2.1.21).

ext2 is the high performance disk file system used by Linux for

fixed disks as well as removable media. The second extended file system was designed as an extension of the extended file system (ext). ext2 offers the best performance (in terms of speed and CPU usage) of the file systems supported under Linux.

ext3 is a journaling version of the ext2 file system. It is easy

to switch back and forth between ext2 and ext3.

ext4 is a set of upgrades to ext3 including substantial

performance and reliability enhancements, plus large increases in volume, file, and directory size limits.

Reiserfs is a journaling file system, designed by Hans Reiser, that

was integrated into Linux in kernel 2.4.1.

XFS is a journaling file system, developed by SGI, that was

integrated into Linux in kernel 2.4.20.

JFS is a journaling file system, developed by IBM, that was

integrated into Linux in kernel 2.4.24.

xiafs was designed and implemented to be a stable, safe file system

by extending the Minix file system code. It provides the basic most requested features without undue complexity. The xia file system is no longer actively developed or maintained. It was removed from the kernel in 2.1.21.

msdos is the file system used by DOS, Windows, and some OS/2

computers. msdos filenames can be no longer than 8 characters, followed by an optional period and 3 character extension.

umsdos is an extended DOS file system used by Linux. It adds

capability for long filenames, UID/GID, POSIX permissions, and special files (devices, named pipes, etc.) under the DOS file system, without sacrificing compatibility with DOS.

vfat is an extended DOS file system used by Microsoft Windows95

and Windows NT. VFAT adds the capability to use long filenames under the MSDOS file system.

ntfs replaces Microsoft Window's FAT file systems (VFAT, FAT32).

It has reliability, performance, and space-utilization enhancements plus features like ACLs, journaling, encryption, and so on.

proc is a pseudo file system which is used as an interface to

kernel data structures rather than reading and interpreting /dev/kmem. In particular, its files do not take disk space. See proc(5).

iso9660 is a CD-ROM file system type conforming to the ISO 9660

standard.

High Sierra

Linux supports High Sierra, the precursor to the ISO 9660 standard for CD-ROM file systems. It is automatically recognized within the iso9660 filesystem support under Linux.

Rock Ridge

Linux also supports the System Use Sharing Protocol records specified by the Rock Ridge Interchange Protocol. They are used to further describe the files in the iso9660 file system to a Unix host, and provide information such as long filenames, UID/GID, POSIX permissions, and devices. It is automatically recognized within the iso9660 file-system support under Linux.

hpfs is the High Performance Filesystem, used in OS/2. This file

system is read-only under Linux due to the lack of available documentation.

sysv is an implementation of the SystemV/Coherent file system for

Linux. It implements all of Xenix FS, SystemV/386 FS, and Coherent FS.

nfs is the network file system used to access disks located on

remote computers.

smb is a network file system that supports the SMB protocol, used

by Windows for Workgroups, Windows NT, and Lan Manager.

To use smb fs, you need a special mount program, which can be found in the ksmbfs package, found at ftp://sunsite.unc.edu/pub/Linux/system/Filesystems/smbfs.

ncpfs is a network file system that supports the NCP protocol, used

by Novell NetWare.

To use ncpfs, you need special programs, which can be found at ftp://linux01.gwdg.de/pub/ncpfs.

SEE ALSO

proc(5), fsck(8), mkfs(8), mount(8)

COLOPHON

This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.

Linux 2010-05-24 FILESYSTEMS(5)