DISKPART(8)						      System Manager's Manual						       DISKPART(8)

NAME

       diskpart - calculate default disk partition sizes

SYNOPSIS

       /usr/sbin/diskpart [ -p ] [ -d ] disk-type

DESCRIPTION

       Diskpart  is  used to calculate the disk partition sizes based on the default rules used at Berkeley.  If the -p option is supplied, tables
       suitable for inclusion in a device driver are produced.	If the -d option is supplied, an entry suitable for inclusion in the disk descrip-
       tion  file  /etc/disktab  is  generated; c.f.  disktab(5).  On disks that use bad144-style bad-sector forwarding, space is left in the last
       partition on the disk for a bad sector forwarding table.  The space reserved is one track for the replicated copies of the table and suffi-
       cient tracks to hold a pool of 126 sectors to which bad sectors are mapped.  For more information, see bad144(8).

       The  disk  partition sizes are based on the total amount of space on the disk as given in the table below (all values are supplied in units
       of 512 byte sectors).  The `c' partition is, by convention, used to access the entire physical disk.  The device driver tables include  the
       space  reserved	for  the  bad sector forwarding table in the `c' partition; those used in the disktab and default formats exclude reserved
       tracks.	In normal operation, either the `g' partition is used, or the `d', `e', and `f' partitions are used.  The `g' and  `f'	partitions
       are  variable-sized,  occupying	whatever  space  remains  after  allocation of the fixed sized partitions.  If the disk is smaller than 20
       Megabytes, then diskpart aborts with the message ``disk too small, calculate by hand''.

	    Partition  20-60 MB  61-205 MB  206-355 MB	356+ MB
	    a	       15884	 15884	    15884	15884
	    b	       10032	 33440	    33440	66880
	    d	       15884	 15884	    15884	15884
	    e	       unused	 55936	    55936	307200
	    h	       unused	 unused     291346	291346

       If an unknown disk type is specified, diskpart will prompt for the required disk geometry information.

SEE ALSO

       disktab(5), bad144(8)

BUGS

       Certain default partition sizes are based on historical artifacts (e.g. RP06), and may result in unsatisfactory layouts.

       When using the -d flag, alternate disk names are not included in the output.

4th Berkeley Distribution					 November 17, 1996						       DISKPART(8)