NAME

       xfs_metadump - copy XFS filesystem metadata to a file

SYNOPSIS

       xfs_metadump [ -aefFgow ] [ -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

       -a     Copies entire metadata blocks.  Normally, xfs_metadump will zero any stale bytes interspersed with
              in-use  metadata.   Use  this  option  to  copy  full  metadata  blocks, to provide more debugging
              information for a corrupted filesystem.  Note that the extra data will be unobfuscated.

       -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.

                                                                                                 xfs_metadump(8)