NAME

diskpart − calculate default disk partition sizes

SYNOPSIS

/etc/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 description file /etc/disktab is generated; c.f.  disktab(5).

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”. 

 Partition20-60 MB61-222 MB223-355 MB356+ MB
a15884158841588415884
b33440334406688066880
dunused158841588415884
eunused5593655936307200
hunusedunused291346291346
 

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

SEE ALSO

disktab(5)

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. 

NEWS-OSRelease 3.3