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NAME

       xfs_copy - copy the contents of an XFS filesystem

SYNOPSIS

       xfs_copy [ -bd ] [ -L log ] source target1 [ target2 ... ]

DESCRIPTION

       xfs_copy  copies  an  XFS filesystem to one or more targets in parallel
       (see xfs(5)).  The first (source) argument must be the pathname of  the
       device  or  file containing the XFS filesystem. The remaining arguments
       specify one or more target devices or  file  names.  If  the  pathnames
       specify devices, a copy of the source XFS filesystem is created on each
       device. The target can also be the name of a  regular  file,  in  which
       case  an image of the source XFS filesystem is created in that file. If
       the file does not exist, xfs_copy creates the file. The length  of  the
       resulting  file is equal to the size of the source filesystem. However,
       if the file is created on an XFS filesystem, the file consumes  roughly
       the  amount  of  space  actually  used  in the source filesystem by the
       filesystem and the XFS log.  The space saving is because xfs_copy seeks
       over  free  blocks  instead  of  copying  them  and  the XFS filesystem
       supports sparse files efficiently.

       xfs_copy should only be used to copy unmounted  filesystems,  read-only
       mounted   filesystems,   or  frozen  filesystems  (see  xfs_freeze(8)).
       Otherwise,  the  generated  filesystem(s)  would  be  inconsistent   or
       corrupt.

       xfs_copy  does  not  alter  the  source filesystem in any way. Each new
       (target) filesystem is identical to the original filesystem except that
       new  filesystems  each  have a new unique filesystem identifier (UUID).
       Therefore, if both the old and new filesystems will be used as separate
       distinct  filesystems,  xfs_copy  or xfsdump(8)/xfsrestore(8) should be
       used to generate the  new  filesystem(s)  instead  of  dd(1)  or  other
       programs that do block-by-block disk copying.

       xfs_copy  uses  synchronous  writes  to  ensure  that  write errors are
       detected.

       xfs_copy uses pthreads(7)  to  perform  simultaneous  parallel  writes.
       xfs_copy  creates  one additional thread for each target to be written.
       All threads die if xfs_copy terminates or aborts.

OPTIONS

       -d     Create a duplicate (true clone) filesystem. This should be  done
              only if the new filesystem will be used as a replacement for the
              original filesystem (such as in the case of disk replacement).

       -b     The buffered option can be used  to  ensure  direct  IO  is  not
              attempted  to  any  of the target files. This is useful when the
              filesystem holding the target file does not support direct IO.

       -L log Specifies the location of the log if  the  default  location  of
              /var/tmp/xfs_copy.log.XXXXXX is not desired.

DIAGNOSTICS

       xfs_copy  reports  errors to both stderr and in more detailed form to a
       generated    log    file    whose    name    is     of     the     form
       /var/tmp/xfs_copy.log.XXXXXX  or a log file specified by the -L option.
       If xfs_copy detects a write error on a target, the  copy  of  that  one
       target is aborted and an error message is issued to both stderr and the
       log  file,  but  the  rest  of  the  copies  continue.  When   xfs_copy
       terminates, all aborted targets are reported to both stderr and the log
       file.

       If all targets abort or  if  there  is  an  error  reading  the  source
       filesystem, xfs_copy immediately aborts.

       xfs_copy  returns  an  exit  code  of 0 if all targets are successfully
       copied and an exit code of 1 if any target fails.

NOTES

       When moving filesystems from one  disk  to  another,  if  the  original
       filesystem  is  significantly smaller than the new filesystem, and will
       be    made    larger,    we    recommend    that    mkfs.xfs(8)     and
       xfsdump(8)/xfsrestore(8)   be   used  instead  of  using  xfs_copy  and
       xfs_growfs(8).    The   filesystem   layout   resulting   from    using
       xfs_copy/xfs_growfs  is  almost  always  worse than the result of using
       mkfs.xfs/xfsdump/xfsrestore but in the case of small  filesystems,  the
       differences  can  have a significant performance impact. This is due to
       the way xfs_growfs(8) works, and not due to any shortcoming in xfs_copy
       itself.

CAVEATS

       xfs_copy does not copy XFS filesystems that have a real-time section or
       XFS filesystems with external logs. In both cases, xfs_copy aborts with
       an error message.

SEE ALSO

       mkfs.xfs(8),  xfsdump(8),  xfsrestore(8), xfs_freeze(8), xfs_growfs(8),
       xfs(5).

                                                                   xfs_copy(8)