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.TH "o2image" "8" "September 2010" "Version @VERSION@" "OCFS2 Manual Pages"
.SH "NAME"
o2image \- Copy or restore \fIOCFS2\fR file system meta-data
.SH "SYNOPSIS"
\fBo2image\fR [\fB\-r\fR] [\fB\-I\fR] \fIdevice\fR \fIimage-file\fR
.SH "DESCRIPTION"
.PP
\fBo2image\fR copies the \fIOCFS2\fR file system meta-data from the device to the specified image-file.
This image file contains the file system skeleton that includes the inodes, directory names
and file names. It does \fBnot\fR include any file data.
This image file can be useful to debug certain problems that are not reproducible otherwise.
Like on-disk corruptions. It could also be used to analyse the file system layout in an aging
file system with an eye towards improving performance.
As the image-file contains a copy of all the meta-data blocks, it can be a large file.
By default, it is created in a packed format, in which all meta-data blocks are written
back-to-back. With the \fB\-r\fR option, the user could choose to have the file in the
raw (or sparse) format, in which the blocks are written to the same offset as they are
on the device.
\fIdebugfs.ocfs2\fR understands both formats.
\fBo2image\fR also has the option, \fI\-I\fR, to restore the meta-data from the image
file onto the device. This option will rarely be useful to end-users and has been written
specifically for developers and testers.
.SH "OPTIONS"
.TP
\fB\-r\fR
Copies the meta-data to the image-file in the raw format. Use this option only if
the destination file system supports sparse files. If unsure, do not use this option
and let the tool create the image-file in the packed format.
.TP
\fB\-I\fR
Restores meta-data from the image-file onto the device. \fBCAUTION: This option could
corrupt the file system.\fR
.TP
\fB\-i\fR
Interactive mode - before writing out the image file print it's size and ask whether to proceed. This setting only applies when '-I' is not specified. It can be useful when the file system holding the image is low on disk space and the user might need to free up space once the target image size is calculated.
.SH "EXAMPLES"
.TS
;
L.
[root@node1 ~]# o2image /dev/sda1 sda1.out
Copies metadata blocks from /dev/sda1 device to sda1.out file
[root@node1 ~] o2image -I /dev/sda1 sda1.out
\fBUse with CAUTION\fR. Copies meta-data blocks from sda1.out onto the
/dev/sda1 device.
.TE
.SH "SEE ALSO"
.BR debugfs.ocfs2(8)
.BR fsck.ocfs2(8)
.SH "AUTHORS"
Oracle Corporation
.SH "COPYRIGHT"
Copyright \(co 2007, 2010 Oracle. All rights reserved.
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