diskpart.8

<B>Digital的Unix操作系统VAX 4.2源码</B>

.\" SCCSID: @(#)diskpart.8	8.1	9/11/90
.TH diskpart 8 "" "" Unsupported
.SH Name
diskpart \- calculate default disk partition sizes
.SH Syntax
.B /etc/diskpart
[
.B \-p
] [
.B \-d
]
disk-type
.SH Description
.NXR "diskpart command"
.NXR "disk partition" "calculating default size"
The
.PN diskpart
command
is used to calculate the disk partition sizes based on the
default rules used at Berkeley.  If the
.B \-p
option is supplied, tables suitable for inclusion in a device driver
are produced.  If the
.B \-d
option is supplied, an entry suitable for inclusion in the disk
description file 
.PN /etc/disktab
is generated.  For further information, see disktab(5).
Space is always 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
sufficient tracks to hold a pool of 126 sectors to which bad sectors
are mapped.  For more information, see 
.MS bad144 8 .
.PP
The disk partition sizes are based on the total amount of
space on the disk as give in the table below (all values
are supplied in units of 512 byte sectors).  
.NXR "disk partition" "disk space and"
The `c' partition
is, by convention, used to access the entire physical disk, including
the space reserved for the bad sector forwarding table.
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
.PN diskpart
aborts with the message ``disk too small, calculate by hand''.
.EX 0
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

.EE
.PP
If an unknown disk type is specified, 
.PN diskpart
prompts for the required disk geometry information.
.SH Restrictions
Certain default partition sizes are based on historical artifacts
(for example, RP06), and may result in unsatisfactory layouts.
.PP
When using the \-d flag, alternate disk names are not included
in the output.
.PP
The
.PN diskpart
command does not understand how to handle drives attached to the
controllers described on the
.MS ra 4
reference page (MSCP disk interface).
.SH See Also
disktab(5), bad144(8), chpt(8)