BTRFS-MAP-LOGICAL(8) System Manager's Manual BTRFS-MAP-LOGICAL(8)NAME
btrfs-map-logical - map btrfs logical extent to physical extent
btrfs-map-logical [options] <device>
btrfs-map-logical can be used to find out what the physical offsets are on the mirrors, the result is dumped into stdout in default.
Logical extent to map.
Copy of the extent to read(usually 1 or 2).
Output file to hold the extent.
Number of bytes to read.
btrfs-map-logical will return 0 if no error happened. If any problems happened, 1 will be returned.
Written by Shilong Wang and Wenruo Qu.
Copyright (C) 2013 Fujitsu, Inc. License GPLv2: GNU GPL version 2 <http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO mkfs.btrfs(8)BTRFS-MAP-LOGICAL(8)
Check Out this Related Man Page
BTRFS-IMAGE(8) System Manager's Manual BTRFS-IMAGE(8)NAME
btrfs-image - create/restore an image of the filesystem
btrfs-image [options] source target
btrfs-image is used to create an image of a btrfs filesystem. All data will be zeroed, but metadata and the like is preserved. source is
the special file corresponding to the device containing a btrfs filesystem. (e.g /dev/sdXX). target is the image file that btrfs-image
creates. When used with -r option, btrfs-image restores the image file from source into target.
OPTIONS -r restore metadump image.
compression level (0 ~ 9).
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.
btrfs-image is part of btrfs-progs. Btrfs is currently under heavy development, and not suitable for any uses other than benchmarking and
review. Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for further details.
SEE ALSO btrfsck(8),mkfs.btrfs(8)BTRFS-IMAGE(8)
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