NAME¶
xfs_metadump - copy XFS filesystem metadata to a file
SYNOPSIS¶
xfs_metadump [
-efFgow ] [
-m max_extents ] ] [
-l logdev ]
source target
xfs_metadump -V
DESCRIPTION¶
xfs_metadump is a debugging tool that copies the metadata from an XFS
filesystem to a file. The
source argument must be the pathname of the
device or file containing the XFS filesystem and the
target argument
specifies the destination file name. If
target is -, then the output is
sent to stdout. This allows the output to be redirected to another program
such as a compression application.
xfs_metadump may only be used to copy unmounted filesystems, or read-only
mounted filesystems.
xfs_metadump does not alter the source filesystem in any way. The
target image is a contiguous (non-sparse) file containing all the
filesystem's metadata and indexes to where the blocks were copied from.
By default,
xfs_metadump obfuscates most file (regular file, directory
and symbolic link) names and extended attribute names to allow the dumps to be
sent without revealing confidential information. Extended attribute values are
zeroed and no data is copied. The only exceptions are file or attribute names
that are 4 or less characters in length. Also file names that span extents
(this can only occur with the
mkfs.xfs(8) options where
-n
size >
-b size) are not obfuscated. Names between 5
and 8 characters in length inclusively are partially obfuscated.
xfs_metadump should not be used for any purposes other than for debugging
and reporting filesystem problems. The most common usage scenario for this
tool is when
xfs_repair(8) fails to repair a filesystem and a metadump
image can be sent for analysis.
The file generated by
xfs_metadump can be restored to filesystem image
(minus the data) using the
xfs_mdrestore(8) tool.
OPTIONS¶
- -e
- Stops the dump on a read error. Normally, it will ignore read errors and
copy all the metadata that is accessible.
- -f
- Specifies that the filesystem image to be processed is stored in a regular
file (see the mkfs.xfs -d file option). This can also happen if an
image copy of a filesystem has been made into an ordinary file with
xfs_copy(8).
- -F
- Specifies that we want to continue even if the superblock magic is not
correct. If the source is truly not an XFS filesystem, the resulting image
will be useless, and xfs_metadump may crash.
- -g
- Shows dump progress. This is sent to stdout if the target is a file
or to stderr if the target is stdout.
- -l logdev
- For filesystems which use an external log, this specifies the device where
the external log resides. The external log is not copied, only internal
logs are copied.
- -m
- Set the maximum size of an allowed metadata extent. Extremely large
metadata extents are likely to be corrupt, and will be skipped if they
exceed this value. The default size is 1000 blocks.
- -o
- Disables obfuscation of file names and extended attributes.
- -w
- Prints warnings of inconsistent metadata encountered to stderr. Bad
metadata is still copied.
- -V
- Prints the version number and exits.
DIAGNOSTICS¶
xfs_metadump returns an exit code of 0 if all readable metadata is
successfully copied or 1 if a write error occurs or a read error occurs and
the
-e option used.
NOTES¶
As
xfs_metadump copies metadata only, it does not matter if the
source filesystem has a realtime section or not. If the filesystem has
an external log, it is not copied. Internal logs are copied and any
outstanding log transactions are not obfuscated if they contain names.
xfs_metadump is a shell wrapper around the
xfs_db(8)
metadump command.
SEE ALSO¶
xfs_repair(8),
xfs_mdrestore(8),
xfs_freeze(8),
xfs_db(8),
xfs_copy(8),
xfs(5)
BUGS¶
Email bug reports to
xfs@oss.sgi.com.