Make intelligible:
Describe the command formats in English. Add references to other programs (boot0cfg, fdisk). Remove some old cruft, including FUD about single-level bootstraps. Add example of output format. Not-objected-to-by: msmith rnordier
This commit is contained in:
parent
755292ace1
commit
4cbdc63443
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=49306
@ -33,11 +33,11 @@
|
||||
.\" SUCH DAMAGE.
|
||||
.\"
|
||||
.\" @(#)disklabel.8 8.2 (Berkeley) 4/19/94
|
||||
.\" $Id: disklabel.8,v 1.9 1998/11/28 09:43:31 rnordier Exp $
|
||||
.\" $Id: disklabel.8,v 1.10 1998/12/17 16:50:10 jkh Exp $
|
||||
.\"
|
||||
.Dd April 19, 1994
|
||||
.Dd July 30, 1999
|
||||
.Dt DISKLABEL 8
|
||||
.Os BSD 4.2
|
||||
.Os FreeBSD
|
||||
.Sh NAME
|
||||
.Nm disklabel
|
||||
.Nd read and write disk pack label
|
||||
@ -66,7 +66,7 @@
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Op Fl s Ar boot2
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk
|
||||
.Oo Ar disktype Oc
|
||||
@ -75,7 +75,7 @@
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Op Fl s Ar boot2
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar disktype
|
||||
.Oo Ar packid Oc
|
||||
@ -84,42 +84,64 @@
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Op Fl s Ar boot2
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar protofile
|
||||
.Oo Ar disktype Oc
|
||||
.Sh DESCRIPTION
|
||||
.Nm Disklabel
|
||||
can be used to install, examine or modify the label on a disk drive or pack.
|
||||
When writing the label, it can be used
|
||||
to change the drive identification,
|
||||
the disk partitions on the drive,
|
||||
or to replace a damaged label.
|
||||
On some systems,
|
||||
installs, examines or modifes the label on a disk drive or pack. When writing
|
||||
the label, it can be used to change the drive identification, the disk
|
||||
partitions on the drive, or to replace a damaged label. There are several forms
|
||||
of the command that read (display), install or edit the label on a disk. In
|
||||
addition,
|
||||
.Nm
|
||||
can be used to install bootstrap code as well.
|
||||
There are several forms of the command that read (display), install or edit
|
||||
the label on a disk.
|
||||
Each form has an additional option,
|
||||
.Fl r ,
|
||||
which causes the label to be read from or written to the disk directly,
|
||||
rather than going through the system's in-core copy of the label.
|
||||
This option may allow a label to be installed on a disk
|
||||
without kernel support for a label, such as when labels are first installed
|
||||
on a system; it must be used when first installing a label on a disk.
|
||||
The specific effect of
|
||||
can install bootstrap code.
|
||||
.Ss Raw or in-core label
|
||||
.Pp
|
||||
The disk label is resident close to or at the beginning of each disk partition.
|
||||
For faster access, the kernel maintains a copy in core at all times. By
|
||||
default, most
|
||||
.Nm
|
||||
access the in-core copy of the label. To access the raw (on-disk) copy, use the
|
||||
.Fl r
|
||||
option. This option allows a label to be installed on a disk without kernel
|
||||
support for a label, such as when labels are first installed on a system; it
|
||||
must be used when first installing a label on a disk. The specific effect of
|
||||
.Fl r
|
||||
is described under each command.
|
||||
The read and install forms also support the
|
||||
.Fl B
|
||||
option to install bootstrap code.
|
||||
These variants are described later.
|
||||
.Pp
|
||||
The first form of the command (read) is used to examine the label on the named
|
||||
disk drive (e.g. da0 or /dev/rda0c).
|
||||
It will display all of the parameters associated with the drive
|
||||
and its partition layout.
|
||||
Unless the
|
||||
.Ss Disk device name
|
||||
.Pp
|
||||
All
|
||||
.Nm disklabel
|
||||
forms require a disk device name, which should always be the raw
|
||||
.if t ``complete'' (or ``c'')
|
||||
.if n "complete" (or "c")
|
||||
partition, for example
|
||||
.Pa /dev/rda0c .
|
||||
.Nm
|
||||
understands the abbreviation
|
||||
.Pa da0 ,
|
||||
which it converts internally to
|
||||
.Pa /dev/rda0c .
|
||||
.Ss Reading the disk label
|
||||
.Pp
|
||||
To examine or save the label on a disk drive, use
|
||||
.Nm
|
||||
without options:
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Op Fl r
|
||||
.Ar disk
|
||||
.Pp
|
||||
.Ar disk
|
||||
represents the raw disk in question, and may be in the form
|
||||
.Pa da0
|
||||
or
|
||||
.Pa /dev/rda0c .
|
||||
It will display all of the parameters associated with the drive and its
|
||||
partition layout. Unless the
|
||||
.Fl r
|
||||
flag is given,
|
||||
the kernel's in-core copy of the label is displayed;
|
||||
@ -127,31 +149,35 @@ if the disk has no label, or the partition types on the disk are incorrect,
|
||||
the kernel may have constructed or modified the label.
|
||||
If the
|
||||
.Fl r
|
||||
flag is given, the label from the raw disk will be displayed rather
|
||||
than the in-core label.
|
||||
flag is given,
|
||||
.Nm
|
||||
reads the label from the raw disk and displays it.
|
||||
.Ss Writing a standard label
|
||||
.Pp
|
||||
The second form of the command, with the
|
||||
To write a standard label, use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl w
|
||||
flag, is used to write a standard label on the designated drive.
|
||||
.Op Fl r
|
||||
.Ar disk Ar disktype
|
||||
.Oo Ar packid Oc
|
||||
.Pp
|
||||
The required arguments to
|
||||
.Nm
|
||||
are the drive to be labeled (e.g. da0), and
|
||||
the drive type as described in the
|
||||
.Xr disktab 5
|
||||
file.
|
||||
The drive parameters and partitions are taken from that file.
|
||||
If different disks of the same physical type are to have different
|
||||
partitions, it will be necessary to have separate disktab entries
|
||||
describing each, or to edit the label after installation as described below.
|
||||
The optional argument is a pack identification string,
|
||||
up to 16 characters long.
|
||||
The pack id must be quoted if it contains blanks.
|
||||
If the
|
||||
are the drive to be labeled and the drive type as described in the
|
||||
.Pa disktab(5)
|
||||
file. The drive parameters and partitions are taken from that file. If
|
||||
different disks of the same physical type are to have different partitions, it
|
||||
will be necessary to have separate disktab entries describing each, or to edit
|
||||
the label after installation as described below. The optional argument is a
|
||||
pack identification string, up to 16 characters long. The pack id must be
|
||||
quoted if it contains blanks. If the
|
||||
.Fl r
|
||||
flag is given, the disk sectors containing the label and bootstrap
|
||||
will be written directly.
|
||||
A side-effect of this is that any existing bootstrap code will be overwritten
|
||||
and the disk rendered unbootable.
|
||||
and the disk rendered unbootable. See the boot options below for a method of
|
||||
writing the label and the bootstrap at the same time.
|
||||
If
|
||||
.Fl r
|
||||
is not specified,
|
||||
@ -176,172 +202,347 @@ disk is the only supported operation, and the
|
||||
.Ar disk
|
||||
itself must be provided as the canonical name, i.e. not as a full
|
||||
path name.
|
||||
.Ss Editing an existing disk label
|
||||
.Pp
|
||||
An existing disk label may be edited by using the
|
||||
To edit an existing disk label, use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl e
|
||||
flag.
|
||||
The label is read from the in-core kernel copy,
|
||||
or directly from the disk if the
|
||||
.Op Fl r
|
||||
.Ar disk
|
||||
.Pp
|
||||
This command reads the label from the in-core kernel copy, or directly from the
|
||||
disk if the
|
||||
.Fl r
|
||||
flag is also given.
|
||||
The label is formatted and then supplied to an editor for changes.
|
||||
If no editor is specified in an
|
||||
flag is also specified. The label is written to a file in ASCII and then
|
||||
supplied to an editor for changes. If no editor is specified in an
|
||||
.Ev EDITOR
|
||||
environment variable,
|
||||
.Xr vi 1
|
||||
is used.
|
||||
When the editor terminates, the formatted label is reread
|
||||
and used to rewrite the disk label.
|
||||
Existing bootstrap code is unchanged regardless of whether
|
||||
is used. When the editor terminates, the label file is used to rewrite the disk
|
||||
label. Existing bootstrap code is unchanged regardless of whether
|
||||
.Fl r
|
||||
was specified.
|
||||
.Ss Restoring a disk label from a file
|
||||
.Pp
|
||||
With the
|
||||
To restore a disk label from a file, use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl R
|
||||
flag,
|
||||
.Nm
|
||||
is capable of restoring a disk label that was formatted
|
||||
in a prior operation and saved in an ascii file.
|
||||
The prototype file used to create the label should be in the same format
|
||||
as that produced when reading or editing a label.
|
||||
Comments are delimited by
|
||||
.Ar \&#
|
||||
and newline.
|
||||
As with
|
||||
.Fl w ,
|
||||
any existing bootstrap code will be clobbered if
|
||||
.Fl r
|
||||
is specified and will be unaffected otherwise.
|
||||
.Op Fl r
|
||||
.Ar disk Ar protofile
|
||||
.Pp
|
||||
The
|
||||
.Fl NW
|
||||
flags for
|
||||
.Nm
|
||||
explicitly disallow and
|
||||
allow, respectively, writing of the pack label area on the selected disk.
|
||||
is capable of restoring a disk label that was previously saved in a file ASCII.
|
||||
The prototype file used to create the label should be in the same format as that
|
||||
produced when reading or editing a label. Comments are delimited by
|
||||
.Ar \&#
|
||||
and newline. As when writing a new label, any existing bootstrap code will be
|
||||
clobbered if
|
||||
.Fl r
|
||||
is specified and will be unaffected otherwise. See the boot options below for a
|
||||
method of restoring the label and writing the bootstrap at the same time.
|
||||
.Ss Enabling and disabling writing to the disk label area
|
||||
.Pp
|
||||
By default, it is not possible to write to the disk label area at the beginning
|
||||
of a disk. The disk driver silently ignores any attempt to do so. If you need
|
||||
to write to this area (for example, to obliterate the label), use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Op Fl W
|
||||
.Ar disk
|
||||
.Pp
|
||||
To disallow writing to the label area after previously allowing it, use the
|
||||
command
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Op Fl N
|
||||
.Ar disk
|
||||
.Ss Installing bootstraps
|
||||
.Pp
|
||||
The final three forms of
|
||||
.Nm
|
||||
are used to install bootstrap code on machines where the bootstrap is part
|
||||
of the label.
|
||||
The bootstrap code is comprised of one or two boot programs depending on
|
||||
the machine.
|
||||
The
|
||||
are used to install bootstrap code:
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl B
|
||||
option is used to denote that bootstrap code is to be installed.
|
||||
The
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk
|
||||
.Oo Ar disktype Oc
|
||||
.Pp
|
||||
This form installs the bootstrap only. It does not change the disk label.
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl w
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar disktype
|
||||
.Oo Ar packid Oc
|
||||
.Pp
|
||||
.if t This form corresponds to the ``write label'' command described above.
|
||||
.if n This form corresponds to the "write label" command described above.
|
||||
In addition to writing a new volume label, it also installs the bootstrap.
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl R
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar protofile
|
||||
.Oo Ar disktype Oc
|
||||
.Pp
|
||||
.if t This form corresponds to the ``restore label'' command described above.
|
||||
.if n This form corresponds to the "restore label" command described above.
|
||||
In addition to restoring the volume label, it also installs the bootstrap.
|
||||
.Pp
|
||||
The bootstrap commands always access the disk directly, so it is not necessary
|
||||
to specify the
|
||||
.Fl r
|
||||
flag is implied by
|
||||
.Fl B
|
||||
and never needs to be specified.
|
||||
The name of the boot program(s) to be installed can be selected in a
|
||||
variety of ways.
|
||||
First, the names can be specified explicitly via the
|
||||
flag.
|
||||
.Pp
|
||||
The bootstrap code is comprised of two boot programs. Specify the name of the
|
||||
boot programs to be installed in one of these ways:
|
||||
.Bl -enum
|
||||
.It
|
||||
Specify the names explicitly with the
|
||||
.Fl b
|
||||
and
|
||||
.Fl s
|
||||
flags.
|
||||
On machines with only a single level of boot program,
|
||||
.Fl b
|
||||
is the name of that program.
|
||||
For machines with a two-level bootstrap,
|
||||
.Fl b
|
||||
indicates the primary boot program and
|
||||
.Fl s
|
||||
the secondary boot program.
|
||||
If the names are not explicitly given, standard boot programs will be used.
|
||||
The boot programs are located in
|
||||
the secondary boot program. The boot programs are located in
|
||||
.Pa /boot .
|
||||
The names of the programs are taken from the ``b0'' and ``b1'' parameters
|
||||
of the
|
||||
.Xr disktab 5
|
||||
entry for the disk if
|
||||
.It
|
||||
If the
|
||||
.Fl b
|
||||
and
|
||||
.Fl s
|
||||
flags are not specified, but
|
||||
.Ar disktype
|
||||
was given and its disktab entry exists and includes those parameters.
|
||||
Otherwise, the default boot image names are used, these being:
|
||||
was specified, the names of the programs are taken from the
|
||||
.if t ``b0'' and ``b1''
|
||||
.if n "b0" and "b1"
|
||||
parameters of the
|
||||
.Xr disktab 5
|
||||
entry for the disk if the disktab entry exists and includes those parameters.
|
||||
.It
|
||||
Otherwise, the default boot image names are used:
|
||||
.Pa /boot/boot1
|
||||
and
|
||||
.Pa /boot/boot2
|
||||
for the standard stage1 and stage2 boot images (details may vary
|
||||
on architectures like the Alpha, where only a single-stage boot is used).
|
||||
.El
|
||||
.Ss The booteasy bootstrap manager
|
||||
.Pp
|
||||
The first of the three boot-installation forms is used to install
|
||||
bootstrap code without changing the existing label.
|
||||
It is essentially a read command with respect to the disk label
|
||||
itself and all options are related to the specification of the boot
|
||||
program as described previously.
|
||||
The final two forms are analogous to the basic write and restore versions
|
||||
except that they will install bootstrap code in addition to a new label.
|
||||
FreeBSD supplies a boot manager called
|
||||
.Nm booteasy
|
||||
which resides in the Master Boot Record. Use the
|
||||
.Nm boot0cfg
|
||||
program to install it.
|
||||
.Sh FILES
|
||||
.Bl -tag -width Pa -compact
|
||||
.It Pa /etc/disktab
|
||||
.It Pa /boot/
|
||||
.It Pa /boot/boot<n>
|
||||
.El
|
||||
.Sh SAVED FILE FORMAT
|
||||
.Nm
|
||||
uses an ASCII version of the label when examining, editing or restoring a disk
|
||||
label. The format is:
|
||||
.Bd -literal -offset 4n
|
||||
# /dev/rda1c:
|
||||
type: SCSI
|
||||
disk: sd0s1
|
||||
label:
|
||||
flags:
|
||||
bytes/sector: 512
|
||||
sectors/track: 51
|
||||
tracks/cylinder: 19
|
||||
sectors/cylinder: 969
|
||||
cylinders: 1211
|
||||
sectors/unit: 1173930
|
||||
rpm: 3600
|
||||
interleave: 1
|
||||
trackskew: 0
|
||||
cylinderskew: 0
|
||||
headswitch: 0 # milliseconds
|
||||
track-to-track seek: 0 # milliseconds
|
||||
drivedata: 0
|
||||
|
||||
8 partitions:
|
||||
# size offset fstype [fsize bsize bps/cpg]
|
||||
a: 81920 0 4.2BSD 1024 8192 16 # (Cyl. 0 - 84*)
|
||||
b: 160000 81920 swap # (Cyl. 84* - 218*)
|
||||
c: 1173930 0 unused 0 0 # (Cyl. 0 - 1211*)
|
||||
h: 962010 211920 vinum # (Cyl. 218*- 1211*)
|
||||
.Ed
|
||||
.Pp
|
||||
Lines starting with a # mark are comments. Most of the other specifications are
|
||||
no longer used. The ones which must still be set correctly are:
|
||||
.Pp
|
||||
.Bl -hang -width 20n
|
||||
.It Nm label
|
||||
is an optional label, set by the
|
||||
.Ar packid
|
||||
option when writing a label.
|
||||
.It Nm flags
|
||||
Flags may be
|
||||
.Ar removable ,
|
||||
.Ar ecc
|
||||
or
|
||||
.Ar badsect .
|
||||
.Ar removable
|
||||
is set for removable media drives, but no current FreeBSD driver evaluates this
|
||||
flag.
|
||||
.Ar ecc
|
||||
is no longer supported;
|
||||
.Ar badsect
|
||||
specifies that the drive can perform bad sector remapping.
|
||||
.It Nm sectors/unit
|
||||
describes the total size of the disk. This value must be correct.
|
||||
.It Nm the partition table
|
||||
This is the UNIX partition table, not the Microsoft partition table described in
|
||||
.Xr fdisk 8 .
|
||||
.El
|
||||
.Pp
|
||||
The partition table can have up to 8 entries. It contains the following
|
||||
information:
|
||||
.Bl -hang -width 10n
|
||||
.It identifier
|
||||
The partition identifier is a single letter in the range
|
||||
.Nm a
|
||||
to
|
||||
.Nm h .
|
||||
By convention, partition
|
||||
.Nm c
|
||||
is reserved to describe the entire disk.
|
||||
.It size
|
||||
is the size of the partition in sectors.
|
||||
.It offset
|
||||
is the offset of the start of the partition from the beginning of the drive.
|
||||
.It fstype
|
||||
describes the purpose of the partition. The example shows most normal usages.
|
||||
For UFS file systems, use type 4.2BSD. See
|
||||
.Pa /usr/include/sys/disklabel.h
|
||||
for a complete list.
|
||||
.It fsize
|
||||
For file systems only, the fragment size.
|
||||
.It bsize
|
||||
For file systems only, the block size.
|
||||
.It bps/cpg
|
||||
For UFS file systems, the number of cylinders in a cylinder group. For LFS file
|
||||
systems, the segment shift value.
|
||||
.El
|
||||
The remainder of the line is a comment and shows the cylinder allocations based
|
||||
on the obsolete (but possibly correct) geometry information about the drive.
|
||||
The asterisk (*) indicates that the partition does not begin or end exactly on a
|
||||
cylinder boundary.
|
||||
.Sh EXAMPLES
|
||||
.Dl disklabel da0
|
||||
.Pp
|
||||
Display the in-core label for da0 as obtained via
|
||||
Display the in-core label for
|
||||
.Pa da0
|
||||
as obtained via
|
||||
.Pa /dev/rda0c .
|
||||
.Pp
|
||||
.Dl disklabel da0 > savedlabel
|
||||
.Pp
|
||||
Save the in-core label for
|
||||
.Pa da0
|
||||
into the file
|
||||
.Pa savedlabel .
|
||||
This file can be used with the
|
||||
.Fl R
|
||||
flag to restore the label at a later date.
|
||||
.Pp
|
||||
.Dl disklabel -w -r /dev/rda0c da2212 foo
|
||||
.Pp
|
||||
Create a label for da0 based on information for ``da2212'' found in
|
||||
Create a label for
|
||||
.Pa da0
|
||||
based on information for
|
||||
.if t ``da2212'' found in
|
||||
.if n "da2212" found in
|
||||
.Pa /etc/disktab .
|
||||
Any existing bootstrap code will be clobbered.
|
||||
.Pp
|
||||
.Dl disklabel -e -r da0
|
||||
.Pp
|
||||
Read the on-disk label for da0, edit it and reinstall in-core as well
|
||||
as on-disk.
|
||||
Existing bootstrap code is unaffected.
|
||||
Read the on-disk label for
|
||||
.Pa da0 ,
|
||||
edit it and reinstall in-core as well as on-disk. Existing bootstrap code is
|
||||
unaffected.
|
||||
.Pp
|
||||
.Dl disklabel -r -w da0 auto
|
||||
.Pp
|
||||
Try to auto-detect the required information from da0, and write a new
|
||||
label to the disk. Use another disklabel -e command to edit the
|
||||
Try to auto-detect the required information from
|
||||
.Pa da0 ,
|
||||
and write a new label to the disk. Use another disklabel -e command to edit the
|
||||
partitioning and file system information.
|
||||
.Pp
|
||||
.Dl disklabel -R da0 mylabel
|
||||
.Dl disklabel -R da0 savedlabel
|
||||
.Pp
|
||||
Restore the on-disk and in-core label for da0 from information in
|
||||
.Pa mylabel .
|
||||
Restore the on-disk and in-core label for
|
||||
.Pa da0
|
||||
from information in
|
||||
.Pa savedlabel .
|
||||
Existing bootstrap code is unaffected.
|
||||
.Pp
|
||||
.Dl disklabel -B da0
|
||||
.Pp
|
||||
Install a new bootstrap on da0.
|
||||
Install a new bootstrap on
|
||||
.Pa da0 .
|
||||
The boot code comes from
|
||||
.Pa /boot/boot1
|
||||
and possibly
|
||||
.Pa /boot/boot2 .
|
||||
On-disk and in-core labels are unchanged.
|
||||
.Pp
|
||||
.Dl disklabel -w -B /dev/rda0c -b newboot da2212
|
||||
.Dl disklabel -w -B /dev/rda0c -b newboot1 -s newboot da2212
|
||||
.Pp
|
||||
Install a new label and bootstrap.
|
||||
The label is derived from disktab information for ``da2212'' and
|
||||
.if t The label is derived from disktab information for ``da2212'' and
|
||||
.if n The label is derived from disktab information for "da2212" and
|
||||
installed both in-core and on-disk.
|
||||
The bootstrap code comes from the file
|
||||
.Pa /boot/newboot .
|
||||
The bootstrap code comes from the files
|
||||
.Pa /boot/newboot1
|
||||
and
|
||||
.Pa /boot/newboot2 .
|
||||
.Sh SEE ALSO
|
||||
.Xr boot0cfg 8 ,
|
||||
.Xr disklabel 5 ,
|
||||
.Xr disktab 5
|
||||
.Xr disktab 5 ,
|
||||
.Xr fdisk 8 .
|
||||
.Sh DIAGNOSTICS
|
||||
The kernel device drivers will not allow the size of a disk partition
|
||||
to be decreased or the offset of a partition to be changed while it is open.
|
||||
Some device drivers create a label containing only a single large partition
|
||||
if a disk is unlabeled; thus, the label must be written to the ``a''
|
||||
partition of the disk while it is open.
|
||||
This sometimes requires the desired label to be set in two steps,
|
||||
the first one creating at least one other partition,
|
||||
and the second setting the label on the new partition
|
||||
while shrinking the ``a'' partition.
|
||||
if a disk is unlabeled; thus, the label must be written to the
|
||||
.if t ``a''
|
||||
.if n "a"
|
||||
partition of the disk while it is open. This sometimes requires the desired
|
||||
label to be set in two steps, the first one creating at least one other
|
||||
partition, and the second setting the label on the new partition while shrinking
|
||||
the
|
||||
.if t ``a''
|
||||
.if n "a"
|
||||
partition.
|
||||
.Pp
|
||||
On some machines the bootstrap code may not fit entirely in the area
|
||||
allocated for it by some filesystems.
|
||||
As a result, it may not be possible to have filesystems on some partitions
|
||||
of a ``bootable'' disk.
|
||||
.if t of a ``bootable'' disk.
|
||||
.if n of a "bootable" disk.
|
||||
When installing bootstrap code,
|
||||
.Nm
|
||||
checks for these cases.
|
||||
@ -355,8 +556,8 @@ Conversely, if a partition has a type other than FS_UNUSED or FS_BOOT,
|
||||
will not install bootstrap code that overlaps it.
|
||||
.Sh BUGS
|
||||
When a disk name is given without a full pathname,
|
||||
the constructed device name uses the ``a'' partition on the Tahoe,
|
||||
the ``c'' partition on all others.
|
||||
.if t the constructed device name uses the ``c'' partition.
|
||||
.if n the constructed device name uses the "c" partition.
|
||||
.Pp
|
||||
For the i386 architecture, the primary bootstrap sector contains
|
||||
an embedded
|
||||
@ -377,3 +578,7 @@ thus replacing the
|
||||
table by the dummy one in the bootstrap program. This is only of
|
||||
concern if the disk is fully dedicated, so that the BSD disklabel
|
||||
starts at absolute block 0 on the disk.
|
||||
.Pp
|
||||
.Nm
|
||||
does not perform adequate error checking. No warning is given if partitions
|
||||
overlap, nor if space remains unused.
|
||||
|
@ -33,11 +33,11 @@
|
||||
.\" SUCH DAMAGE.
|
||||
.\"
|
||||
.\" @(#)disklabel.8 8.2 (Berkeley) 4/19/94
|
||||
.\" $Id: disklabel.8,v 1.9 1998/11/28 09:43:31 rnordier Exp $
|
||||
.\" $Id: disklabel.8,v 1.10 1998/12/17 16:50:10 jkh Exp $
|
||||
.\"
|
||||
.Dd April 19, 1994
|
||||
.Dd July 30, 1999
|
||||
.Dt DISKLABEL 8
|
||||
.Os BSD 4.2
|
||||
.Os FreeBSD
|
||||
.Sh NAME
|
||||
.Nm disklabel
|
||||
.Nd read and write disk pack label
|
||||
@ -66,7 +66,7 @@
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Op Fl s Ar boot2
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk
|
||||
.Oo Ar disktype Oc
|
||||
@ -75,7 +75,7 @@
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Op Fl s Ar boot2
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar disktype
|
||||
.Oo Ar packid Oc
|
||||
@ -84,42 +84,64 @@
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Op Fl s Ar boot2
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar protofile
|
||||
.Oo Ar disktype Oc
|
||||
.Sh DESCRIPTION
|
||||
.Nm Disklabel
|
||||
can be used to install, examine or modify the label on a disk drive or pack.
|
||||
When writing the label, it can be used
|
||||
to change the drive identification,
|
||||
the disk partitions on the drive,
|
||||
or to replace a damaged label.
|
||||
On some systems,
|
||||
installs, examines or modifes the label on a disk drive or pack. When writing
|
||||
the label, it can be used to change the drive identification, the disk
|
||||
partitions on the drive, or to replace a damaged label. There are several forms
|
||||
of the command that read (display), install or edit the label on a disk. In
|
||||
addition,
|
||||
.Nm
|
||||
can be used to install bootstrap code as well.
|
||||
There are several forms of the command that read (display), install or edit
|
||||
the label on a disk.
|
||||
Each form has an additional option,
|
||||
.Fl r ,
|
||||
which causes the label to be read from or written to the disk directly,
|
||||
rather than going through the system's in-core copy of the label.
|
||||
This option may allow a label to be installed on a disk
|
||||
without kernel support for a label, such as when labels are first installed
|
||||
on a system; it must be used when first installing a label on a disk.
|
||||
The specific effect of
|
||||
can install bootstrap code.
|
||||
.Ss Raw or in-core label
|
||||
.Pp
|
||||
The disk label is resident close to or at the beginning of each disk partition.
|
||||
For faster access, the kernel maintains a copy in core at all times. By
|
||||
default, most
|
||||
.Nm
|
||||
access the in-core copy of the label. To access the raw (on-disk) copy, use the
|
||||
.Fl r
|
||||
option. This option allows a label to be installed on a disk without kernel
|
||||
support for a label, such as when labels are first installed on a system; it
|
||||
must be used when first installing a label on a disk. The specific effect of
|
||||
.Fl r
|
||||
is described under each command.
|
||||
The read and install forms also support the
|
||||
.Fl B
|
||||
option to install bootstrap code.
|
||||
These variants are described later.
|
||||
.Pp
|
||||
The first form of the command (read) is used to examine the label on the named
|
||||
disk drive (e.g. da0 or /dev/rda0c).
|
||||
It will display all of the parameters associated with the drive
|
||||
and its partition layout.
|
||||
Unless the
|
||||
.Ss Disk device name
|
||||
.Pp
|
||||
All
|
||||
.Nm disklabel
|
||||
forms require a disk device name, which should always be the raw
|
||||
.if t ``complete'' (or ``c'')
|
||||
.if n "complete" (or "c")
|
||||
partition, for example
|
||||
.Pa /dev/rda0c .
|
||||
.Nm
|
||||
understands the abbreviation
|
||||
.Pa da0 ,
|
||||
which it converts internally to
|
||||
.Pa /dev/rda0c .
|
||||
.Ss Reading the disk label
|
||||
.Pp
|
||||
To examine or save the label on a disk drive, use
|
||||
.Nm
|
||||
without options:
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Op Fl r
|
||||
.Ar disk
|
||||
.Pp
|
||||
.Ar disk
|
||||
represents the raw disk in question, and may be in the form
|
||||
.Pa da0
|
||||
or
|
||||
.Pa /dev/rda0c .
|
||||
It will display all of the parameters associated with the drive and its
|
||||
partition layout. Unless the
|
||||
.Fl r
|
||||
flag is given,
|
||||
the kernel's in-core copy of the label is displayed;
|
||||
@ -127,31 +149,35 @@ if the disk has no label, or the partition types on the disk are incorrect,
|
||||
the kernel may have constructed or modified the label.
|
||||
If the
|
||||
.Fl r
|
||||
flag is given, the label from the raw disk will be displayed rather
|
||||
than the in-core label.
|
||||
flag is given,
|
||||
.Nm
|
||||
reads the label from the raw disk and displays it.
|
||||
.Ss Writing a standard label
|
||||
.Pp
|
||||
The second form of the command, with the
|
||||
To write a standard label, use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl w
|
||||
flag, is used to write a standard label on the designated drive.
|
||||
.Op Fl r
|
||||
.Ar disk Ar disktype
|
||||
.Oo Ar packid Oc
|
||||
.Pp
|
||||
The required arguments to
|
||||
.Nm
|
||||
are the drive to be labeled (e.g. da0), and
|
||||
the drive type as described in the
|
||||
.Xr disktab 5
|
||||
file.
|
||||
The drive parameters and partitions are taken from that file.
|
||||
If different disks of the same physical type are to have different
|
||||
partitions, it will be necessary to have separate disktab entries
|
||||
describing each, or to edit the label after installation as described below.
|
||||
The optional argument is a pack identification string,
|
||||
up to 16 characters long.
|
||||
The pack id must be quoted if it contains blanks.
|
||||
If the
|
||||
are the drive to be labeled and the drive type as described in the
|
||||
.Pa disktab(5)
|
||||
file. The drive parameters and partitions are taken from that file. If
|
||||
different disks of the same physical type are to have different partitions, it
|
||||
will be necessary to have separate disktab entries describing each, or to edit
|
||||
the label after installation as described below. The optional argument is a
|
||||
pack identification string, up to 16 characters long. The pack id must be
|
||||
quoted if it contains blanks. If the
|
||||
.Fl r
|
||||
flag is given, the disk sectors containing the label and bootstrap
|
||||
will be written directly.
|
||||
A side-effect of this is that any existing bootstrap code will be overwritten
|
||||
and the disk rendered unbootable.
|
||||
and the disk rendered unbootable. See the boot options below for a method of
|
||||
writing the label and the bootstrap at the same time.
|
||||
If
|
||||
.Fl r
|
||||
is not specified,
|
||||
@ -176,172 +202,347 @@ disk is the only supported operation, and the
|
||||
.Ar disk
|
||||
itself must be provided as the canonical name, i.e. not as a full
|
||||
path name.
|
||||
.Ss Editing an existing disk label
|
||||
.Pp
|
||||
An existing disk label may be edited by using the
|
||||
To edit an existing disk label, use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl e
|
||||
flag.
|
||||
The label is read from the in-core kernel copy,
|
||||
or directly from the disk if the
|
||||
.Op Fl r
|
||||
.Ar disk
|
||||
.Pp
|
||||
This command reads the label from the in-core kernel copy, or directly from the
|
||||
disk if the
|
||||
.Fl r
|
||||
flag is also given.
|
||||
The label is formatted and then supplied to an editor for changes.
|
||||
If no editor is specified in an
|
||||
flag is also specified. The label is written to a file in ASCII and then
|
||||
supplied to an editor for changes. If no editor is specified in an
|
||||
.Ev EDITOR
|
||||
environment variable,
|
||||
.Xr vi 1
|
||||
is used.
|
||||
When the editor terminates, the formatted label is reread
|
||||
and used to rewrite the disk label.
|
||||
Existing bootstrap code is unchanged regardless of whether
|
||||
is used. When the editor terminates, the label file is used to rewrite the disk
|
||||
label. Existing bootstrap code is unchanged regardless of whether
|
||||
.Fl r
|
||||
was specified.
|
||||
.Ss Restoring a disk label from a file
|
||||
.Pp
|
||||
With the
|
||||
To restore a disk label from a file, use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl R
|
||||
flag,
|
||||
.Nm
|
||||
is capable of restoring a disk label that was formatted
|
||||
in a prior operation and saved in an ascii file.
|
||||
The prototype file used to create the label should be in the same format
|
||||
as that produced when reading or editing a label.
|
||||
Comments are delimited by
|
||||
.Ar \&#
|
||||
and newline.
|
||||
As with
|
||||
.Fl w ,
|
||||
any existing bootstrap code will be clobbered if
|
||||
.Fl r
|
||||
is specified and will be unaffected otherwise.
|
||||
.Op Fl r
|
||||
.Ar disk Ar protofile
|
||||
.Pp
|
||||
The
|
||||
.Fl NW
|
||||
flags for
|
||||
.Nm
|
||||
explicitly disallow and
|
||||
allow, respectively, writing of the pack label area on the selected disk.
|
||||
is capable of restoring a disk label that was previously saved in a file ASCII.
|
||||
The prototype file used to create the label should be in the same format as that
|
||||
produced when reading or editing a label. Comments are delimited by
|
||||
.Ar \&#
|
||||
and newline. As when writing a new label, any existing bootstrap code will be
|
||||
clobbered if
|
||||
.Fl r
|
||||
is specified and will be unaffected otherwise. See the boot options below for a
|
||||
method of restoring the label and writing the bootstrap at the same time.
|
||||
.Ss Enabling and disabling writing to the disk label area
|
||||
.Pp
|
||||
By default, it is not possible to write to the disk label area at the beginning
|
||||
of a disk. The disk driver silently ignores any attempt to do so. If you need
|
||||
to write to this area (for example, to obliterate the label), use the form
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Op Fl W
|
||||
.Ar disk
|
||||
.Pp
|
||||
To disallow writing to the label area after previously allowing it, use the
|
||||
command
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Op Fl N
|
||||
.Ar disk
|
||||
.Ss Installing bootstraps
|
||||
.Pp
|
||||
The final three forms of
|
||||
.Nm
|
||||
are used to install bootstrap code on machines where the bootstrap is part
|
||||
of the label.
|
||||
The bootstrap code is comprised of one or two boot programs depending on
|
||||
the machine.
|
||||
The
|
||||
are used to install bootstrap code:
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl B
|
||||
option is used to denote that bootstrap code is to be installed.
|
||||
The
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk
|
||||
.Oo Ar disktype Oc
|
||||
.Pp
|
||||
This form installs the bootstrap only. It does not change the disk label.
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl w
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar disktype
|
||||
.Oo Ar packid Oc
|
||||
.Pp
|
||||
.if t This form corresponds to the ``write label'' command described above.
|
||||
.if n This form corresponds to the "write label" command described above.
|
||||
In addition to writing a new volume label, it also installs the bootstrap.
|
||||
.Pp
|
||||
.Nm disklabel
|
||||
.Fl R
|
||||
.Fl B
|
||||
.Oo
|
||||
.Fl b Ar boot1
|
||||
.Fl s Ar boot2
|
||||
.Oc
|
||||
.Ar disk Ar protofile
|
||||
.Oo Ar disktype Oc
|
||||
.Pp
|
||||
.if t This form corresponds to the ``restore label'' command described above.
|
||||
.if n This form corresponds to the "restore label" command described above.
|
||||
In addition to restoring the volume label, it also installs the bootstrap.
|
||||
.Pp
|
||||
The bootstrap commands always access the disk directly, so it is not necessary
|
||||
to specify the
|
||||
.Fl r
|
||||
flag is implied by
|
||||
.Fl B
|
||||
and never needs to be specified.
|
||||
The name of the boot program(s) to be installed can be selected in a
|
||||
variety of ways.
|
||||
First, the names can be specified explicitly via the
|
||||
flag.
|
||||
.Pp
|
||||
The bootstrap code is comprised of two boot programs. Specify the name of the
|
||||
boot programs to be installed in one of these ways:
|
||||
.Bl -enum
|
||||
.It
|
||||
Specify the names explicitly with the
|
||||
.Fl b
|
||||
and
|
||||
.Fl s
|
||||
flags.
|
||||
On machines with only a single level of boot program,
|
||||
.Fl b
|
||||
is the name of that program.
|
||||
For machines with a two-level bootstrap,
|
||||
.Fl b
|
||||
indicates the primary boot program and
|
||||
.Fl s
|
||||
the secondary boot program.
|
||||
If the names are not explicitly given, standard boot programs will be used.
|
||||
The boot programs are located in
|
||||
the secondary boot program. The boot programs are located in
|
||||
.Pa /boot .
|
||||
The names of the programs are taken from the ``b0'' and ``b1'' parameters
|
||||
of the
|
||||
.Xr disktab 5
|
||||
entry for the disk if
|
||||
.It
|
||||
If the
|
||||
.Fl b
|
||||
and
|
||||
.Fl s
|
||||
flags are not specified, but
|
||||
.Ar disktype
|
||||
was given and its disktab entry exists and includes those parameters.
|
||||
Otherwise, the default boot image names are used, these being:
|
||||
was specified, the names of the programs are taken from the
|
||||
.if t ``b0'' and ``b1''
|
||||
.if n "b0" and "b1"
|
||||
parameters of the
|
||||
.Xr disktab 5
|
||||
entry for the disk if the disktab entry exists and includes those parameters.
|
||||
.It
|
||||
Otherwise, the default boot image names are used:
|
||||
.Pa /boot/boot1
|
||||
and
|
||||
.Pa /boot/boot2
|
||||
for the standard stage1 and stage2 boot images (details may vary
|
||||
on architectures like the Alpha, where only a single-stage boot is used).
|
||||
.El
|
||||
.Ss The booteasy bootstrap manager
|
||||
.Pp
|
||||
The first of the three boot-installation forms is used to install
|
||||
bootstrap code without changing the existing label.
|
||||
It is essentially a read command with respect to the disk label
|
||||
itself and all options are related to the specification of the boot
|
||||
program as described previously.
|
||||
The final two forms are analogous to the basic write and restore versions
|
||||
except that they will install bootstrap code in addition to a new label.
|
||||
FreeBSD supplies a boot manager called
|
||||
.Nm booteasy
|
||||
which resides in the Master Boot Record. Use the
|
||||
.Nm boot0cfg
|
||||
program to install it.
|
||||
.Sh FILES
|
||||
.Bl -tag -width Pa -compact
|
||||
.It Pa /etc/disktab
|
||||
.It Pa /boot/
|
||||
.It Pa /boot/boot<n>
|
||||
.El
|
||||
.Sh SAVED FILE FORMAT
|
||||
.Nm
|
||||
uses an ASCII version of the label when examining, editing or restoring a disk
|
||||
label. The format is:
|
||||
.Bd -literal -offset 4n
|
||||
# /dev/rda1c:
|
||||
type: SCSI
|
||||
disk: sd0s1
|
||||
label:
|
||||
flags:
|
||||
bytes/sector: 512
|
||||
sectors/track: 51
|
||||
tracks/cylinder: 19
|
||||
sectors/cylinder: 969
|
||||
cylinders: 1211
|
||||
sectors/unit: 1173930
|
||||
rpm: 3600
|
||||
interleave: 1
|
||||
trackskew: 0
|
||||
cylinderskew: 0
|
||||
headswitch: 0 # milliseconds
|
||||
track-to-track seek: 0 # milliseconds
|
||||
drivedata: 0
|
||||
|
||||
8 partitions:
|
||||
# size offset fstype [fsize bsize bps/cpg]
|
||||
a: 81920 0 4.2BSD 1024 8192 16 # (Cyl. 0 - 84*)
|
||||
b: 160000 81920 swap # (Cyl. 84* - 218*)
|
||||
c: 1173930 0 unused 0 0 # (Cyl. 0 - 1211*)
|
||||
h: 962010 211920 vinum # (Cyl. 218*- 1211*)
|
||||
.Ed
|
||||
.Pp
|
||||
Lines starting with a # mark are comments. Most of the other specifications are
|
||||
no longer used. The ones which must still be set correctly are:
|
||||
.Pp
|
||||
.Bl -hang -width 20n
|
||||
.It Nm label
|
||||
is an optional label, set by the
|
||||
.Ar packid
|
||||
option when writing a label.
|
||||
.It Nm flags
|
||||
Flags may be
|
||||
.Ar removable ,
|
||||
.Ar ecc
|
||||
or
|
||||
.Ar badsect .
|
||||
.Ar removable
|
||||
is set for removable media drives, but no current FreeBSD driver evaluates this
|
||||
flag.
|
||||
.Ar ecc
|
||||
is no longer supported;
|
||||
.Ar badsect
|
||||
specifies that the drive can perform bad sector remapping.
|
||||
.It Nm sectors/unit
|
||||
describes the total size of the disk. This value must be correct.
|
||||
.It Nm the partition table
|
||||
This is the UNIX partition table, not the Microsoft partition table described in
|
||||
.Xr fdisk 8 .
|
||||
.El
|
||||
.Pp
|
||||
The partition table can have up to 8 entries. It contains the following
|
||||
information:
|
||||
.Bl -hang -width 10n
|
||||
.It identifier
|
||||
The partition identifier is a single letter in the range
|
||||
.Nm a
|
||||
to
|
||||
.Nm h .
|
||||
By convention, partition
|
||||
.Nm c
|
||||
is reserved to describe the entire disk.
|
||||
.It size
|
||||
is the size of the partition in sectors.
|
||||
.It offset
|
||||
is the offset of the start of the partition from the beginning of the drive.
|
||||
.It fstype
|
||||
describes the purpose of the partition. The example shows most normal usages.
|
||||
For UFS file systems, use type 4.2BSD. See
|
||||
.Pa /usr/include/sys/disklabel.h
|
||||
for a complete list.
|
||||
.It fsize
|
||||
For file systems only, the fragment size.
|
||||
.It bsize
|
||||
For file systems only, the block size.
|
||||
.It bps/cpg
|
||||
For UFS file systems, the number of cylinders in a cylinder group. For LFS file
|
||||
systems, the segment shift value.
|
||||
.El
|
||||
The remainder of the line is a comment and shows the cylinder allocations based
|
||||
on the obsolete (but possibly correct) geometry information about the drive.
|
||||
The asterisk (*) indicates that the partition does not begin or end exactly on a
|
||||
cylinder boundary.
|
||||
.Sh EXAMPLES
|
||||
.Dl disklabel da0
|
||||
.Pp
|
||||
Display the in-core label for da0 as obtained via
|
||||
Display the in-core label for
|
||||
.Pa da0
|
||||
as obtained via
|
||||
.Pa /dev/rda0c .
|
||||
.Pp
|
||||
.Dl disklabel da0 > savedlabel
|
||||
.Pp
|
||||
Save the in-core label for
|
||||
.Pa da0
|
||||
into the file
|
||||
.Pa savedlabel .
|
||||
This file can be used with the
|
||||
.Fl R
|
||||
flag to restore the label at a later date.
|
||||
.Pp
|
||||
.Dl disklabel -w -r /dev/rda0c da2212 foo
|
||||
.Pp
|
||||
Create a label for da0 based on information for ``da2212'' found in
|
||||
Create a label for
|
||||
.Pa da0
|
||||
based on information for
|
||||
.if t ``da2212'' found in
|
||||
.if n "da2212" found in
|
||||
.Pa /etc/disktab .
|
||||
Any existing bootstrap code will be clobbered.
|
||||
.Pp
|
||||
.Dl disklabel -e -r da0
|
||||
.Pp
|
||||
Read the on-disk label for da0, edit it and reinstall in-core as well
|
||||
as on-disk.
|
||||
Existing bootstrap code is unaffected.
|
||||
Read the on-disk label for
|
||||
.Pa da0 ,
|
||||
edit it and reinstall in-core as well as on-disk. Existing bootstrap code is
|
||||
unaffected.
|
||||
.Pp
|
||||
.Dl disklabel -r -w da0 auto
|
||||
.Pp
|
||||
Try to auto-detect the required information from da0, and write a new
|
||||
label to the disk. Use another disklabel -e command to edit the
|
||||
Try to auto-detect the required information from
|
||||
.Pa da0 ,
|
||||
and write a new label to the disk. Use another disklabel -e command to edit the
|
||||
partitioning and file system information.
|
||||
.Pp
|
||||
.Dl disklabel -R da0 mylabel
|
||||
.Dl disklabel -R da0 savedlabel
|
||||
.Pp
|
||||
Restore the on-disk and in-core label for da0 from information in
|
||||
.Pa mylabel .
|
||||
Restore the on-disk and in-core label for
|
||||
.Pa da0
|
||||
from information in
|
||||
.Pa savedlabel .
|
||||
Existing bootstrap code is unaffected.
|
||||
.Pp
|
||||
.Dl disklabel -B da0
|
||||
.Pp
|
||||
Install a new bootstrap on da0.
|
||||
Install a new bootstrap on
|
||||
.Pa da0 .
|
||||
The boot code comes from
|
||||
.Pa /boot/boot1
|
||||
and possibly
|
||||
.Pa /boot/boot2 .
|
||||
On-disk and in-core labels are unchanged.
|
||||
.Pp
|
||||
.Dl disklabel -w -B /dev/rda0c -b newboot da2212
|
||||
.Dl disklabel -w -B /dev/rda0c -b newboot1 -s newboot da2212
|
||||
.Pp
|
||||
Install a new label and bootstrap.
|
||||
The label is derived from disktab information for ``da2212'' and
|
||||
.if t The label is derived from disktab information for ``da2212'' and
|
||||
.if n The label is derived from disktab information for "da2212" and
|
||||
installed both in-core and on-disk.
|
||||
The bootstrap code comes from the file
|
||||
.Pa /boot/newboot .
|
||||
The bootstrap code comes from the files
|
||||
.Pa /boot/newboot1
|
||||
and
|
||||
.Pa /boot/newboot2 .
|
||||
.Sh SEE ALSO
|
||||
.Xr boot0cfg 8 ,
|
||||
.Xr disklabel 5 ,
|
||||
.Xr disktab 5
|
||||
.Xr disktab 5 ,
|
||||
.Xr fdisk 8 .
|
||||
.Sh DIAGNOSTICS
|
||||
The kernel device drivers will not allow the size of a disk partition
|
||||
to be decreased or the offset of a partition to be changed while it is open.
|
||||
Some device drivers create a label containing only a single large partition
|
||||
if a disk is unlabeled; thus, the label must be written to the ``a''
|
||||
partition of the disk while it is open.
|
||||
This sometimes requires the desired label to be set in two steps,
|
||||
the first one creating at least one other partition,
|
||||
and the second setting the label on the new partition
|
||||
while shrinking the ``a'' partition.
|
||||
if a disk is unlabeled; thus, the label must be written to the
|
||||
.if t ``a''
|
||||
.if n "a"
|
||||
partition of the disk while it is open. This sometimes requires the desired
|
||||
label to be set in two steps, the first one creating at least one other
|
||||
partition, and the second setting the label on the new partition while shrinking
|
||||
the
|
||||
.if t ``a''
|
||||
.if n "a"
|
||||
partition.
|
||||
.Pp
|
||||
On some machines the bootstrap code may not fit entirely in the area
|
||||
allocated for it by some filesystems.
|
||||
As a result, it may not be possible to have filesystems on some partitions
|
||||
of a ``bootable'' disk.
|
||||
.if t of a ``bootable'' disk.
|
||||
.if n of a "bootable" disk.
|
||||
When installing bootstrap code,
|
||||
.Nm
|
||||
checks for these cases.
|
||||
@ -355,8 +556,8 @@ Conversely, if a partition has a type other than FS_UNUSED or FS_BOOT,
|
||||
will not install bootstrap code that overlaps it.
|
||||
.Sh BUGS
|
||||
When a disk name is given without a full pathname,
|
||||
the constructed device name uses the ``a'' partition on the Tahoe,
|
||||
the ``c'' partition on all others.
|
||||
.if t the constructed device name uses the ``c'' partition.
|
||||
.if n the constructed device name uses the "c" partition.
|
||||
.Pp
|
||||
For the i386 architecture, the primary bootstrap sector contains
|
||||
an embedded
|
||||
@ -377,3 +578,7 @@ thus replacing the
|
||||
table by the dummy one in the bootstrap program. This is only of
|
||||
concern if the disk is fully dedicated, so that the BSD disklabel
|
||||
starts at absolute block 0 on the disk.
|
||||
.Pp
|
||||
.Nm
|
||||
does not perform adequate error checking. No warning is given if partitions
|
||||
overlap, nor if space remains unused.
|
||||
|
Loading…
Reference in New Issue
Block a user