View source for Veritas File System

{{short description|Extent-based file system}}
{{Distinguish|text= the file systems [[XFS]] and [[JFS (file system)|JFS]]}}

{{Infobox filesystem
| name = VERITAS File System
| developer =
| full_name = VERITAS File System
| introduction_date = {{Start date and age|1991}}
| introduction_os =
| partition_id =
| directory_struct = extensible hash
| file_struct =
| bad_blocks_struct =
| max_file_size = {{nowrap|2<sup>63</sup> bytes}} (8 EiB)
| max_files_no =
| max_filename_size = 256 bytes
| max_volume_size = {{nowrap|2<sup>77</sup> bytes}} (128 ZiB)
| dates_recorded =
| date_range =
| date_resolution =
| forks_streams = yes
| attributes = [[Extended file attributes]]
| file_system_permissions = Unix permissions, [[Access control list|ACL]]
| compression = No
| encryption = No
| OS = [[Linux]], [[Solaris (operating system)|Solaris]], [[HP-UX]], [[IBM AIX|AIX]], [[SINIX]], [[UnixWare]]
}}
The '''VERITAS File System''' (or '''VxFS'''; called '''JFS''' and '''OnlineJFS''' in [[HP-UX]]) is an [[extent (file systems)|extent]]-based [[file system]]. It was originally developed by [[VERITAS Software]].<ref>{{cite web
 |url          = http://www.patentstorm.us/patents/6871271.html
 |title        = Incrementally restoring a mass storage device to a prior state
 |date         = 2005-03-22
 |access-date   = 2007-11-21
 |archive-url  = https://web.archive.org/web/20080309193205/http://www.patentstorm.us/patents/6871271.html
 |archive-date = 2008-03-09
 |url-status     = dead
}}</ref>  Through an [[Original equipment manufacturer|OEM]] agreement, VxFS is used as the primary filesystem of the [[HP-UX]] [[operating system]]. With on-line [[defragmentation]] and resize support turned on via license, it is known as ''OnlineJFS''.<ref>{{cite web
   |url=http://mailman.eng.auburn.edu/pipermail/veritas-vx/2000-April/000163.html
   |title=Post in the veritas-vx mailing list explaining the differences between JFS and OJFS
   |author=Donna Yobs
   |date=2000-04-10
   |access-date=2007-11-21
|archive-url = https://web.archive.org/web/20080309165600/http://mailman.eng.auburn.edu/pipermail/veritas-vx/2000-April/000163.html <!-- Bot retrieved archive --> |archive-date = 2008-03-09}}</ref>
It is also supported on [[IBM AIX|AIX]], [[Linux]], [[Solaris (operating system)|Solaris]], [[OpenSolaris]], [[SINIX]]/Reliant UNIX, [[UnixWare]] and [[OpenServer|SCO OpenServer]].{{Citation needed|date=August 2010}} VxFS was originally developed for [[AT&T Corporation|AT&T]]'s [[Unix System Laboratories]].  VxFS is packaged as a part of the [[Veritas Storage Foundation]] (which also includes [[Veritas Volume Manager]]).

==History==
According to the vendor, it was the first commercial [[journaling file system]].<ref>{{cite web |url=http://ftp.support.veritas.com/pub/support/products/FileSystem_UNIX/253148.pdf |title=VERITAS Foundation Suite and Foundation Suite HA 3.5 |publisher=VERITAS |access-date=2007-11-21 |archive-url=https://web.archive.org/web/20031025011156/http://ftp.support.veritas.com/pub/support/products/FileSystem_UNIX/253148.pdf |archive-date=2003-10-25 |url-status=dead }}</ref>
That claim can be taken in two ways, i.e., the first implementation of a journaling file system in a commercial context, or the first file system available as an unbundled product.

[[Dan Koren]] is cited as one of the original developers of VxFS.<ref>{{cite web |url=http://www.linux-kongress.org/1999/abstracts.html |title=6th International Linux Kongress |date=1999-09-09 |access-date=2007-11-21}}</ref>
He notes in a mailing list that they "finished release 1.0 one year or so later" after starting development of VxFS under a contract with [[AT&T Corporation]] in 1990.<ref>{{cite web|url=https://lkml.org/lkml/1999/6/1/31 |title=Re: XFS and journalling filesystems |author=Dan Koren |date=1999-06-01 |publisher=LKML.org |access-date=2007-11-21}}</ref>  Other sources agree that the product was first released in 1991.<ref>{{cite web |url=http://www.byteandswitch.com/document.asp?doc_id=24108&page_number=3 |title=Next-Gen File Systems &mdash; File under 'futuristic': An overview of the technologies and players &mdash; The Heavy Hitters: Veritas |publisher=Byte and Switch |date=2002-11-14 |access-date=2007-11-21 |archive-date=2008-03-09 |archive-url=https://web.archive.org/web/20080309233339/http://www.byteandswitch.com/document.asp?doc_id=24108&page_number=3 |url-status=dead }}</ref><ref>{{cite web |url=http://issj.sys-con.com/read/46369.htm |title=VERITAS Celebrates 15 Years - Next Big Focus: Grid Computing |publisher=SYS-CON |date=2004-09-14 |access-date=2007-11-21 |archive-date=2008-03-11 |archive-url=https://web.archive.org/web/20080311020055/http://issj.sys-con.com/read/46369.htm |url-status=dead }}</ref>

As the internet was not widely available in the early 1990s, getting a new file system deployed for Unix-like operating systems was more difficult, so the one- to two-year delay in the release and commercialization of this file system was not unusual.{{fact|date=April 2017}}

==Version history==
The on-disk layout of VxFS is versioned and upgradeable while the file system is mounted. This file system has gone through ten versions.

* Version 2 added support for filesets, dynamic inode allocation and ACLs. Layouts 1–3 stopped being supported in VxFS 4.0.
* Version 4 added support for storage checkpoints and for [[Veritas Cluster File System]]. Version 4 was released in VxFS 3.2.1. Layout version 4 is no longer supported under VxFS 5.1.<ref name="VxFS-5.1">{{cite web|url=http://seer.entsupport.symantec.com/docs/339064.htm|archive-url=https://web.archive.org/web/20110716174201/http://seer.entsupport.symantec.com/docs/339064.htm|url-status=dead|archive-date=July 16, 2011|title=Veritas File Systems with Disk Layout Version 4 or Version 5 Cannot be Mounted or Upgraded with Veritas File System Release 5.1}}</ref>
* Version 5 started support for file systems up to 32 [[terabyte]]s ({{nowrap|2<sup>45</sup> bytes}}) in size.  Individual files can be up to 2 terabytes in size. Version 5 was introduced in VxFS 3.5 and is no longer supported under VxFS 5.1.<ref name="VxFS-5.1"/>
* Version 6 added support for file systems and files up to 8 [[exabyte]]s ({{nowrap|2<sup>63</sup> bytes}}) in size. Version 6 also introduced support for [[Fork (filesystem)|named streams/resource forks]], for multiple underlying volumes, and for [[File Change Log|file change logs]]. Version 6 was introduced in VxFS 4.0.
* Version 7 extends support for multiple volumes to permit Dynamic Storage Tiering. Dynamic Storage Tiering allows root users to move files among different volumes, allocate files to different volumes at file creation time based on policy, and independently recover volumes, without altering the namespace of the file system. Version 7 was introduced in VxFS 5.0.
* Version 8 enables support for file-level snapshots and shared extents. Version 8 was introduced in VxFS 5.1.
* Version 9 enables support for file compression, deduplication, and partition directories. Version 9 was introduced in VxFS 6.0.
* Version 10 enables support for maxlink, which permits a directory to contain more than 64K subdirectories. Version 10 was introduced in VxFS 6.1.

==Parallel access mode==
VxFS file system can run in ''single instance mode'' or in a ''parallel access / cluster mode''. The parallel mode allows for multiple servers (also known as cluster nodes) to simultaneously access the same file system. When run in this mode, VxFS is referred to as [[Veritas Cluster File System]].

The '''Cluster File System''' provides cache coherency and [[POSIX]] compliance across nodes, so that data changes are atomically seen by all cluster nodes simultaneously. Because Cluster File System shares the same binaries and same on-disk layout as single instance VxFS, moving between cluster and single instance mode is straightforward.

==See also==
* [[Comparison of file systems]]
* [[Symantec Operations Readiness Tools]] (SORT)

==References==
{{Reflist}}



{{Symantec}}
{{Filesystem}}

[[Category:1991 software]]
[[Category:Disk file systems]]
[[Category:Shared disk file systems]]
[[Category:HP software]]
[[Category:File systems supported by the Linux kernel]]