Ext3cow

This article will address the topic of Ext3cow, which has gained great relevance in recent years, due to its impact on various areas of society. Since its appearance, Ext3cow has aroused great interest and generated intense debates in public opinion. Throughout this research, the different aspects related to Ext3cow will be analyzed, as well as its implications in different contexts. The current and future perspectives of Ext3cow will also be addressed, in order to provide a comprehensive vision of this currently significant topic.


ext3cow
Developer(s)Zachary Peterson (ext3cow versioning), Stephen Tweedie (ext3 design and implementation), Rémy Card (original ext2 design and implementation), Theodore Ts'o (tools and improvements), Andreas Gruenbacher (xattrs and ACLs), Andreas Dilger (online resizing), et al.
Full nameThird extended file system with copy-on-write
IntroducedJuly 2003 (2003-07) with Linux
Partition IDs0x83 (MBR)
EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 (GPT)
Structures
Directory contentsTable, Tree
File allocationbitmap (free space), table (metadata)
Bad blocksTable
Limits
Max volume size8TiB
Max file size2TiB
Max no. of filesVariable1
Max filename length255 bytes
Allowed filename
characters		All bytes except NUL, '/' and '@'
Features
Dates recordedmodification (mtime), attribute modification (ctime), access (atime)
Date rangeDecember 14, 1901 - January 18, 2038
Date resolution1s
ForksYes
AttributesNo-atime, append-only, synchronous-write, no-dump, h-tree (directory), immutable, journal, secure-delete, top (directory), allow-undelete
File system
permissions		Unix permissions, ACLs and arbitrary security attributes (Linux 2.6 and later)
Transparent
compression		No
Transparent
encryption		No (provided at the block device level)
Other
Supported
operating systems		Linux

Ext3cow or third extended filesystem with copy-on-write is an open source, versioning file system based on the ext3 file system. Versioning is implemented through block-level copy-on-write. It shares many of its performance characteristics with ext3.

Ext3cow provides a time-shifting interface that permits a real-time and continuous view of data in the past. Time-shifting is a novel interface, introduced in ext3cow, allowing users to navigate through and access past namespaces by adding a time component to their commands.

Ext3cow was designed to be a platform for compliance with the versioning and auditability requirements of recent US electronic record retention legislation, such as Sarbanes-Oxley and HIPAA.

A version of ext3cow for the Linux 2.6 kernel was released on March 30, 2007.

Details on ext3cow's implementation can be found in a 2005 paper.[1]

See also

References

  1. ^ Zachary Peterson and Randal Burns (May 2005). "Ext3cow: A Time-Shifting File System for Regulatory Compliance" (PDF). ACM Transactions on Storage, 1(2). Archived from the original (PDF) on 2011-07-19. Retrieved 2009-02-03.