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btrfs-image(8)


NAME

   btrfs-image - create/restore an image of the filesystem

SYNOPSIS

   btrfs-image [options] <source> <target>

DESCRIPTION

   btrfs-image is used to create an image of a btrfs filesystem. All data
   will be zeroed, but metadata and the like is preserved. Mainly used for
   debugging purposes.

   In the dump mode, source is the btrfs device/file and target is the
   output file (use - for stdout).

   In the restore mode (option -r), source is the dumped image and target
   is the btrfs device/file.

OPTIONS

   -r
       Restore metadump image. By default, this fixes super's chunk tree,
       by using 1 stripe pointing to primary device, so that file system
       can be restored by running tree log reply if possible. To restore
       without changing number of stripes in chunk tree check -o option.

   -c <value>
       Compression level (0 ~ 9).

   -t <value>
       Number of threads (1 ~ 32) to be used to process the image dump or
       restore.

   -o
       Use the old restore method, this does not fixup the chunk tree so
       the restored file system will not be able to be mounted.

   -s
       Sanitize the file names when generating the image. One -s means
       just generate random garbage, which means that the directory
       indexes won't match up since the hashes won't match with the
       garbage filenames. Using -ss will calculate a collision for the
       filename so that the hashes match, and if it can't calculate a
       collision then it will just generate garbage. The collision
       calculator is very time and CPU intensive so only use it if you are
       having problems with your file system tree and need to have it
       mostly working.

   -w
       Walk all the trees manually and copy any blocks that are
       referenced. Use this option if your extent tree is corrupted to
       make sure that all of the metadata is captured.

   -m
       Restore for multiple devices, more than 1 device should be
       provided.

EXIT STATUS

   btrfs-image will return 0 if no error happened. If any problems
   happened, 1 will be returned.

SEE ALSO

   mkfs.btrfs(8)



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