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btrfs-map-logical(8) [centos man page]

BTRFS-MAP-LOGICAL(8)					      System Manager's Manual					      BTRFS-MAP-LOGICAL(8)

NAME
btrfs-map-logical - map btrfs logical extent to physical extent SYNOPSIS
btrfs-map-logical [options] <device> DESCRIPTION
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. Options -l|--logical <logical_num> Logical extent to map. -c|--copy <copy> Copy of the extent to read(usually 1 or 2). -o|--output <filename> Output file to hold the extent. -b|--bytes <bytes> Number of bytes to read. EXIT CODE
btrfs-map-logical will return 0 if no error happened. If any problems happened, 1 will be returned. AUTHOR
Written by Shilong Wang and Wenruo Qu. COPYRIGHT
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

BTRFSCTL(8)						      System Manager's Manual						       BTRFSCTL(8)

NAME
btrfsctl - control a btrfs filesystem SYNOPSIS
btrfsctl [ -d file|directory ] [ -s snapshot-name directory ] [ -S subvolume-name directory ] [ -r [+-]size ] [ -A device ] [ -a ] [ -c ] DESCRIPTION
btrfsctl is used to control the filesystem and the files and directories stored. It is the tool to create a new snapshot for the filesys- tem. OPTIONS
-d file|directory Defragment a file or a directory. If the argument is a directory, the entire b-tree under the directory is defragged. -s snapshot-name directory Creates a new snapshot of the directory specified. -S subvolume-name directory Creates a new subvolume. -r [+|-]size Resizes the filesystem with the size specified. If the value is preceded with a signed symbol, the filesystem is resized with respect to the current filesystem size. size can be suffixed by k,m or g to represent kilobytes, megabytes, or gigabytes respec- tively. -A device Scans the device for btrfs filesystem. -a Scans all devices present in the system for btrfs filesystem. -c Forces a filesystem sync. AVAILABILITY
btrfsctl 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
mkfs.btrfs(8) BTRFSCTL(8)
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