Manual Pages  — FFSINFO

The output is appended to the file outfile. Also expect the output file to be rather large. Up to 2 percent of the size of the specified file system is not uncommon.

The following options are available:

-g cylinder_group
	This restricts the dump to information about this cylinder group only. Here file ... means the first cylinder group and -1 the last one.
-i inode
	This restricts the dump to information about this particular inode only. Here the minimum acceptable inode is 2. If this option is omitted but a cylinder group is defined then only inodes within that cylinder group are dumped.
-l level
	The level of detail which will be dumped. This value defaults to 255 and is the "bitwise or" of the following table:
0x001	initial superblock
0x002	superblock copies in each cylinder group
0x004	cylinder group summary in initial cylinder group
0x008	cylinder group information
0x010	inode allocation bitmap
0x020	fragment allocation bitmap
0x040	cluster maps and summary
0x100	inode information
0x200	indirect block dump

-o outfile
	This sets the output filename where the dump is written to, and must be specified. If - is provided, output will be sent to stdout.