# BTRFS-MAP-LOGICAL - map btrfs logical extent to physical extent - man(8) - [phpMan]

[_BTRFS-MAP-LOGICAL_(8)](https://www.chedong.com/phpMan.php/man/BTRFS-MAP-LOGICAL/8/markdown)                            BTRFS                           [_BTRFS-MAP-LOGICAL_(8)](https://www.chedong.com/phpMan.php/man/BTRFS-MAP-LOGICAL/8/markdown)

## 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 to stdout by default.

       Mainly used for debug purpose.

## 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 STATUS
       **btrfs-map-logical **will return 0 if no error happened.  If any problems happened,  1  will  be
       returned.

## SEE ALSO
       [_mkfs.btrfs(8)](https://www.chedong.com/phpMan.php/man/mkfs.btrfs/8/markdown)_


6.6.3                                       Mar 31, 2024                        [_BTRFS-MAP-LOGICAL_(8)](https://www.chedong.com/phpMan.php/man/BTRFS-MAP-LOGICAL/8/markdown)