GFS2
The Global File System (GFS) is a shared storage file system available for Linux computer clusters.
GFS is different from distributed file systems like AFS, Coda, or InterMezzo because it requires all nodes to have direct concurrent access to the same shared block storage.
GFS has no disconnected operating mode, and no client or server roles. All nodes in a GFS cluster are peers. Fibre Channel, iSCSI, or AoE devices are often used for GFS shared storage. GFS depends on a distributed lock manager like GULM or DLM. GFS is free software, distributed under the terms of the GNU General Public License.
History
GFS originally developed as part of a thesis project at the University of Minnesota. At some point it made its way to Sistina Software, where it lived for a time as an open source project. Sometime in 2001 Sistina made the choice to make GFS a commercial product — not under an open source license.
OpenGFS was forked from the last public release of GFS and was then further developed to include updates allowing it to work with OpenDLM. OpenGFS and OpenDLM are now defunct, since Red Hat purchased Sistina in December 2003 and in late June 2004, released GFS and many cluster infrastructure pieces under the GPL. Red Hat subsequently put forth some more development geared towards bug fixing and stabilization, resulting in the inclusion of GFS and its dedicated distributed lock manager into the version 2.6.19 of the mainline Linux kernel.
GFS now forms part of the Fedora Core distribution and can be purchased as a commercial product on top of Red Hat Enterprise Linux. Here are some version numbers and major features introduced:
- v1.0 (1996) SGI IRIX only
- v3.0 Linux-port
- v4 Journaling
- v5 Redundant Lock Manager
- v6.1 (2005) Distributed Lock Manager
See also
- Comparison of file systems
- Lustre
- List of file systems
- Oracle cluster file system (OCFS)
- SAN file system
External links
Background
- Symmetric Cluster Architecture — paper (pdf) describing gfs and future development
- http://www.diku.dk/undervisning/2003e/314/papers/soltis97global.pdf — a good paper about the technical background of GFS and how it compares to other network filesystems
- Old but still useful GFS 5.1.1 user manual: pdf
Documentation
- Red Hat GFS Product Page
- Red Hat Cluster Suite and GFS Documentation Page
- GFS Project Page
- DataCore's GFS Informations