The chkfsys utility is your principal tool for checking and restoring a potentially damaged filesystem. It can identify and correct a host of minor problems as well as verify the integrity of the disk system as a whole.
Normally, chkfsys requires that the filesystem be idle and that no files be currently open on that device. You'll have to shut down any processes that have opened files or that may need to open files while chkfsys is running.
To run chkfsys on a mountpoint, type:
chkfsys mountpoint
The utility scans the entire disk partition from the root down, building an internal copy of the bitmap and verifying the consistency of all files and directories it finds in the process.
When it has finished processing all files, chkfsys compares the internal bitmap to the bitmap on the disk. If they match, chkfsys is finished. If any discrepancies are found, chkfsys will—upon your approval—rewrite the bitmap with data consistent with the files it was able to find and verify.
In addition to verifying block allocation (bitmap), chkfsys attempts to fix any problems it finds during the scan. For example, chkfsys can: