aufs
| Developer(s) | Junjiro Okajima |
|---|---|
| Full name | Advanced multi layered unification filesystem |
| Introduced | 2006 |
| Features | |
| File system permissions | POSIX |
| Other | |
| Supported operating systems | Linux via third-party kernel module |
aufs (short for advanced multi-layered unification filesystem) implements a union mount for Linux file systems. The name is an acronym which originally stood for AnotherUnionFS, but since version 2 it stands for "advanced multi-layered unification filesystem".
Developed by Junjiro Okajima in 2006,[1] aufs is a complete rewrite of the earlier UnionFS. It aimed to improve reliability and performance, but also introduced some new concepts, like writable branch balancing,[2] and other improvements – some of which are now implemented in the UnionFS 2.x branch.
aufs was rejected for merging into mainline Linux. Its code was criticized for being "dense, unreadable, and uncommented".[3] Instead, OverlayFS was merged in the Linux kernel.[4][5] After several attempts, the author has given it up.[6]
Use
Docker originally used aufs for container filesystem layers. It is still available as one of the supported storage backends.
Several Linux distributions have chosen aufs as a replacement for UnionFS, including:
- Knoppix live CD Linux distribution – since the end of 2006, "for better stability and performance"[7]
- NimbleX since version 2008. Switched simultaneously with Linux-Live
- Porteus LiveCD, run fully in RAM
- Slax (and Linux-Live scripts in general) since version 6[8]
- Xandros Linux distribution, available in the ASUS Eee PC model 901
- Ubuntu 10.04 LTS Live CD
- Debian 6.0 Live media
- Gentoo Linux LiveDVD 11.0[9]
- Gentoo Linux LiveDVD 11.2[10]
- Gentoo Linux LiveDVD 12.0[11]
- Salix Live via Linux-Live scripts until version 13.1.1 and via SaLT from version 13.37
- Puppy Linux versions can run fully in RAM with changes saved to disk on shutdown. For example, Slacko 5.3.3 running as a LiveCD.
See also
- OverlayFS, the competing project that was chosen for merger to the Linux core
- File system
- Union mount, describing the concept of merging file system branches
- UnionFS, an older union mount project
- Syslinux
References
- ↑ "History of aufs". Retrieved 2015-11-08.
- ↑ Goals and new features of aufs in the project's homepage
- ↑ Aurora, Valerie (2009-04-07). "Unioning file systems: Implementations, part 2". LWN.net. Retrieved 2015-11-08.
- ↑ "overlay filesystem · torvalds/linux@e9be9d5". Retrieved 12 July 2016.
- ↑ Hellwig, Christoph (2009-04-10). "Re: [RFC Aufs2 #5 28/29] export lookup functions". Retrieved 2015-11-08.
- ↑ Okajima, Junjiro (2009-04-10). "Re: [RFC Aufs2 #5 28/29] export lookup functions". Retrieved 2015-11-08.
- ↑ "KNOPPIX 5.1 - Live Linux Filesystem On CD". knopper.net. 2013-01-05. Retrieved 2015-11-08.
- ↑ Linux Live scripts use AUFS for better stability
- ↑ "Gentoo Linux - Gentoo Linux - LiveDVD 11.0". Gentoo.org. 2011-03-08. Archived from the original on 2012-04-13. Retrieved 2012-04-19.
- ↑ "Gentoo Linux - Gentoo Linux releases 11.2 LiveDVD". Gentoo.org. 2011-08-07. Archived from the original on 2012-04-17. Retrieved 2012-04-19.
- ↑ "Gentoo Linux - Gentoo Linux releases 12.0 LiveDVD". Gentoo.org. 2012-01-02. Archived from the original on 2012-04-21. Retrieved 2012-04-19.