Documentation: Update filesystems/gfs2.rst (d9593868) · Commits · jan.koester / Linux

Documentation/filesystems/gfs2.rst

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	.. SPDX-License-Identifier: GPL-2.0		.. SPDX-License-Identifier: GPL-2.0

	==================		====================
	Global File System		Global File System 2
	==================		====================

	https://fedorahosted.org/cluster/wiki/HomePage		GFS2 is a cluster file system. It allows a cluster of computers to

	GFS is a cluster file system. It allows a cluster of computers to
	simultaneously use a block device that is shared between them (with FC,		simultaneously use a block device that is shared between them (with FC,
	iSCSI, NBD, etc). GFS reads and writes to the block device like a local		iSCSI, NBD, etc). GFS2 reads and writes to the block device like a local
	file system, but also uses a lock module to allow the computers coordinate		file system, but also uses a lock module to allow the computers coordinate
	their I/O so file system consistency is maintained. One of the nifty		their I/O so file system consistency is maintained. One of the nifty
	features of GFS is perfect consistency -- changes made to the file system		features of GFS2 is perfect consistency -- changes made to the file system
	on one machine show up immediately on all other machines in the cluster.		on one machine show up immediately on all other machines in the cluster.

	GFS uses interchangeable inter-node locking mechanisms, the currently		GFS2 uses interchangeable inter-node locking mechanisms, the currently
	supported mechanisms are:		supported mechanisms are:

	lock_nolock		lock_nolock
	- allows gfs to be used as a local file system		- allows GFS2 to be used as a local file system

	lock_dlm		lock_dlm
	- uses a distributed lock manager (dlm) for inter-node locking.		- uses the distributed lock manager (dlm) for inter-node locking.
	The dlm is found at linux/fs/dlm/		The dlm is found at linux/fs/dlm/

	Lock_dlm depends on user space cluster management systems found		lock_dlm depends on user space cluster management systems found
	at the URL above.		at the URL above.

	To use gfs as a local file system, no external clustering systems are		To use GFS2 as a local file system, no external clustering systems are
	needed, simply::		needed, simply::

	$ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device		$ mkfs -t gfs2 -p lock_nolock -j 1 /dev/block_device
	$ mount -t gfs2 /dev/block_device /dir		$ mount -t gfs2 /dev/block_device /dir

	If you are using Fedora, you need to install the gfs2-utils package		The gfs2-utils package is required on all cluster nodes and, for lock_dlm, you
	and, for lock_dlm, you will also need to install the cman package		will also need the dlm and corosync user space utilities configured as per the
	and write a cluster.conf as per the documentation. For F17 and above		documentation.
	cman has been replaced by the dlm package.
			gfs2-utils can be found at https://pagure.io/gfs2-utils

	GFS2 is not on-disk compatible with previous versions of GFS, but it		GFS2 is not on-disk compatible with previous versions of GFS, but it
	is pretty close.		is pretty close.

	The following man pages can be found at the URL above:		The following man pages are available from gfs2-utils:

	============ =============================================		============ =============================================
	fsck.gfs2 to repair a filesystem		fsck.gfs2 to repair a filesystem
	gfs2_grow to expand a filesystem online		gfs2_grow to expand a filesystem online
	gfs2_jadd to add journals to a filesystem online		gfs2_jadd to add journals to a filesystem online
	tunegfs2 to manipulate, examine and tune a filesystem		tunegfs2 to manipulate, examine and tune a filesystem
	gfs2_convert to convert a gfs filesystem to gfs2 in-place		gfs2_convert to convert a gfs filesystem to GFS2 in-place
	mkfs.gfs2 to make a filesystem		mkfs.gfs2 to make a filesystem
	============ =============================================		============ =============================================