About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / filesystems / gfs2.txt




Custom Search

Based on kernel version 3.15.4. Page generated on 2014-07-07 09:03 EST.

1	Global File System
2	------------------
3	
4	https://fedorahosted.org/cluster/wiki/HomePage
5	
6	GFS is a cluster file system. It allows a cluster of computers to
7	simultaneously use a block device that is shared between them (with FC,
8	iSCSI, NBD, etc).  GFS reads and writes to the block device like a local
9	file system, but also uses a lock module to allow the computers coordinate
10	their I/O so file system consistency is maintained.  One of the nifty
11	features of GFS is perfect consistency -- changes made to the file system
12	on one machine show up immediately on all other machines in the cluster.
13	
14	GFS uses interchangeable inter-node locking mechanisms, the currently
15	supported mechanisms are:
16	
17	  lock_nolock -- allows gfs to be used as a local file system
18	
19	  lock_dlm -- uses a distributed lock manager (dlm) for inter-node locking
20	  The dlm is found at linux/fs/dlm/
21	
22	Lock_dlm depends on user space cluster management systems found
23	at the URL above.
24	
25	To use gfs as a local file system, no external clustering systems are
26	needed, simply:
27	
28	  $ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device
29	  $ mount -t gfs2 /dev/block_device /dir
30	
31	If you are using Fedora, you need to install the gfs2-utils package
32	and, for lock_dlm, you will also need to install the cman package
33	and write a cluster.conf as per the documentation. For F17 and above
34	cman has been replaced by the dlm package.
35	
36	GFS2 is not on-disk compatible with previous versions of GFS, but it
37	is pretty close.
38	
39	The following man pages can be found at the URL above:
40	  fsck.gfs2		to repair a filesystem
41	  gfs2_grow		to expand a filesystem online
42	  gfs2_jadd		to add journals to a filesystem online
43	  tunegfs2		to manipulate, examine and tune a filesystem
44	  gfs2_convert	to convert a gfs filesystem to gfs2 in-place
45	  mkfs.gfs2		to make a filesystem
Hide Line Numbers
About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Information is copyright its respective author. All material is available from the Linux Kernel Source distributed under a GPL License. This page is provided as a free service by mjmwired.net.