Provided by: ufsutils_8.2-3_amd64 bug


     dumpfs — dump file system information


     dumpfs [-f] [-m] filesys | device


     The dumpfs utility prints out the super block and cylinder group information for the file
     system or special device specified, unless the -f or -m flag is specified.  The listing is
     very long and detailed.  This command is useful mostly for finding out certain file system
     information such as the file system block size and minimum free space percentage.

     If -f is specified, a sorted list of all free fragments and free fragment ranges, as
     represented in cylinder group block free lists, is printed.  If the flag is specified twice,
     contiguous free fragments are not collapsed into ranges and instead printed in a simple
     list.  Fragment numbers may be converted to raw byte offsets by multiplying by the fragment
     size, which may be useful when recovering deleted data.

     If -m is specified, a newfs(8) command is printed that can be used to generate a new file
     system with equivalent settings.


     disktab(5), fs(5), disklabel(8), fsck(8), newfs(8), tunefs(8)


     The dumpfs utility appeared in 4.2BSD.