Dumps file system information.
dumpfs { FileSystem | Device }
The dumpfs command prints out the superblock, i-node map, and disk map information for the file system or special device specified. This listing is used to find out file system information. Primarily, the dumpfs command is for debugging purposes.
The dumpfs command can also run against a JFS2 snapshot. The dumpfs command prints out the superblock, snapshot map, and block map xtree copy for the specified snapshot.
To print the information for /dev/hd4, enter:
dumpfs /dev/hd4
The fsck command, mkfs command.