o2info(1)							OCFS2 Manual Pages							 o2info(1)

NAME

       o2info - Dump OCFS2 file system information on disk.

SYNOPSIS

       o2info [-C|--cluster-coherent] [--fs-features] [--volinfo] [--mkfs] <device or file>

DESCRIPTION

       o2info  is designed to be an information tool, to display OCFS2 file system information on disk. Its main goal on one hand, is to provide a
       tool to display fs info in a comprehensive way and providing the information which may be missing in debugfs.ocfs and tunefs.ocfs2 such	as
       global  bitmap  free  space  fragmentation  and free inode info for each slot, on the other hand, it also aims to become a info tool(not an
       administration one), which therefore allows all users who may have no read privilege on the underlying device to use the utility. In  prac-
       tice, 'o2info /path/to/file/on/ocfs2/vol' use a new OCFS2_IOC_INFO ioctl to get info from fs for a mounted case. For a privileged user(e.g,
       root), the same info however, can also be accessed by 'o2info /dev/sdxN' to direcly manipulate the raw device.

OPTIONS

       -C, --cluster-coherent
	      Enable cluster (in)coherency for mounted case, means it will attempt to acquire a global PR lock when querying info from	a  cluster
	      filesystem, which may degrade the performance, default is none cluster-coherency.

       --fs-features
	      List all compat, incompat and ro-compat fs features on OCFS2 filesystem.

       --volinfo
	      Dump basic volume information, such as blocksize, clustersize, volume label and UUID etc.

       --mkfs Dump  an	original  format  of  mkfs.ocfs's  arguments,  importantly,  which can be used directly as a fresh mkfs retry: #mkfs.ocfs2
	      "$(o2info --mkfs /dev/name/or/path/of/file)" /dev/sdaX

       -V, --version
	      Show version and exit.

       -h, --help
	      Display help and exit.

EXAMPLES

       [oracle@node1 ~]# o2info --volinfo /storage/testfile	 # For none-privileged users.
       [root@node1 ~]# o2info --volinfo /dev/sda1
	      Label: ocfs2-volume
	       UUID: 976D8E630B3A4F1F95497311A92901FC
	 Block Size: 4096
       Cluster Size: 4096
	 Node Slots: 4
	   Features: backup-super strict-journal-super sparse inline-data xattr
	   Features: unwritten

SEE ALSO

       debugfs.ocfs2(8) tunefs.ocfs2(8)

AUTHORS

       Oracle Corporation

COPYRIGHT

       Copyright (C) 2010 Oracle. All rights reserved.

Version 1.6.4							   October 2010 							 o2info(1)