blob: 593004b6bbabaeee282b1041835f580cf12baa2e [file] [log] [blame]
David Teiglande4731422006-01-18 09:21:38 +00001Global File System
2------------------
3
4http://sources.redhat.com/cluster/
5
6GFS is a cluster file system. It allows a cluster of computers to
7simultaneously use a block device that is shared between them (with FC,
8iSCSI, NBD, etc). GFS reads and writes to the block device like a local
9file system, but also uses a lock module to allow the computers coordinate
10their I/O so file system consistency is maintained. One of the nifty
11features of GFS is perfect consistency -- changes made to the file system
12on one machine show up immediately on all other machines in the cluster.
13
14GFS uses interchangable inter-node locking mechanisms. Different lock
15modules can plug into GFS and each file system selects the appropriate
16lock module at mount time. Lock modules include:
17
18 lock_nolock -- allows gfs to be used as a local file system
19
20 lock_dlm -- uses a distributed lock manager (dlm) for inter-node locking
21 The dlm is found at linux/fs/dlm/
22
23In addition to interfacing with an external locking manager, a gfs lock
24module is responsible for interacting with external cluster management
25systems. Lock_dlm depends on user space cluster management systems found
26at the URL above.
27
28To use gfs as a local file system, no external clustering systems are
29needed, simply:
30
Steven Whitehouse2fcb4a12006-02-24 10:42:20 -050031 $ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device
David Teiglande4731422006-01-18 09:21:38 +000032 $ mount -t gfs2 /dev/block_device /dir
33
34GFS2 is not on-disk compatible with previous versions of GFS.
35
36The following man pages can be found at the URL above:
David Teiglande4731422006-01-18 09:21:38 +000037 gfs2_fsck to repair a filesystem
38 gfs2_grow to expand a filesystem online
39 gfs2_jadd to add journals to a filesystem online
40 gfs2_tool to manipulate, examine and tune a filesystem
41 gfs2_quota to examine and change quota values in a filesystem
David Teigland373b5a42006-04-25 15:44:04 -040042 mount.gfs2 to help mount(8) mount a filesystem
43 mkfs.gfs2 to make a filesystem