System Administration Guide, Volume 1

How to Format a DOS Diskette

You can format a DOS diskette on a SPARC or IA platform. The steps are similar, except that instead of a SunOS file system being placed on the diskette, a DOS file system, either MS-DOS or NEC-DOS, is put on the diskette.

Caution - Caution -

Formatting a diskette erases any pre-existing content.

  1. Quit File Manager.

    File Manager automatically displays a formatting window when you insert an unformatted diskette. To avoid the window, quit from File Manager. If you prefer to keep File Manager open, quit the formatting window when it appears.

  2. Make sure the diskette is not write-protected.

    On both 3.5-inch and 5.25 inch diskettes, write-protection is controlled by a small tab in either the lower left or lower right corner. If you can see through the square hole behind the tab, the diskette is write-protected. If the hole is covered by the tab, the diskette is write-enabled. (If you need to eject the diskette to examine it, simply type eject floppy in a shell.)

  3. Insert the diskette.

    Make sure the diskette is completely inserted. It must drop down into the drive.

  4. Invoke formatting.

    $ fdformat -v -U [density-options convenience-options]


    Verifies whether the diskette was formatted correctly. 


    Unmounts the diskette if it is mounted. 


    If the drive density is 1.44 Mbytes, density-options are:



    Formats at 1.44 Mbytes for MS-DOS.  


    -d -D

    Formats at 720 Kbytes for MS-DOS. 


    -t nec -M

    Formats at 1.2 Mbytes for NEC-DOS. 



    Lists all the options to the fdformat command, but does not format the diskette.





    Ejects the diskette when done formatting. 



    Does not ask for confirmation before formatting. 


    -b label

    Name for the diskette. label must be eight characters or less, upper or lower case.



    Lists all the options to the fdformat command, but does not format the diskette.

    Note -

    If you try to format a 720 Kbyte (DD) diskette for 1.44 Mbytes, fdformat will not stop you unless you include the -v option. With the -v option, fdformat will format the diskette, but the verification will catch the error and notify you with the following message: fdformat: check diskette density, I/O error

    The fdformat command displays a confirmation message, indicating the type of formatting to be performed:

    Formatting 1.44 M in /vol/dev/rdiskette0/unformatted
    Press return to start formatting floppy.
  5. Select one of the options in the table below.

    To ... 

    Press ... 

    Confirm the type of formatting 

    Return (unless you used the -f option in the previous step, in which case no confirmation is necessary)

    Cancel formatting 


    As the formatting progresses, a series of dots is displayed. As the verification progresses, a series of Vs appears beneath the dots. When the series stops, the formatting is complete and the diskette is ready for use on a DOS system.

  6. Run the volrmmount(1) command using the -i option to notify Volume Management that the diskette is inserted.

    $ volrmmount -i floppy0

    Volume Management mounts the diskette under /floppy/floppy0.

Example--Formatting a DOS Diskette

The following example formats a 1.44 Mbyte MS-DOS diskette and assigns the diskette the name myfiles:

$ fdformat -v -U -b myfiles
Formatting 1.44 M in /vol/dev/rdiskette0/unformatted
Press return to start formatting floppy. [ Return ]