.\" Copyright (c) 2007, 2008 Marcel Moolenaar
.\" All rights reserved.
.\"
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.\" modification, are permitted provided that the following conditions
.\" are met:
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.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" $FreeBSD$
.\"
.Dd August 19, 2011
.Dt GPART 8
.Os
.Sh NAME
.Nm gpart
.Nd "control utility for the disk partitioning GEOM class"
.Sh SYNOPSIS
To add support for the disk partitioning GEOM class,
place one or more of the following
lines in your kernel configuration file:
.Bd -ragged -offset indent
.Cd "options GEOM_PART_APM"
.Cd "options GEOM_PART_BSD"
.Cd "options GEOM_PART_EBR"
.Cd "options GEOM_PART_EBR_COMPAT"
.Cd "options GEOM_PART_GPT"
.Cd "options GEOM_PART_MBR"
.Cd "options GEOM_PART_PC98"
.Cd "options GEOM_PART_VTOC8"
.Ed
.Pp
The
.Dv GEOM_PART_APM
option adds support for the Apple Partition Map (APM)
found on Apple Macintosh computers.
The
.Dv GEOM_PART_BSD
option adds support for the traditional
.Bx
disklabel.
The
.Dv GEOM_PART_EBR
option adds support for the Extended Boot Record (EBR),
which is used to define a logical partition.
The
.Dv GEOM_PART_EBR_COMPAT
option enables backward compatibility for partition names
in the EBR scheme.
Also it makes impossible any types of actions
with such partitions.
The
.Dv GEOM_PART_GPT
option adds support for the GUID Partition Table (GPT)
found on Intel Itanium computers and Intel-based Macintosh computers.
The
.Dv GEOM_PART_MBR
option adds support for the Master Boot Record (MBR)
found on PCs and used on many removable media.
The
.Dv GEOM_PART_PC98
option adds support for the MBR variant as used on
NEC PC-98 computers.
The
.Dv GEOM_PART_VTOC8
option adds support for Sun's SMI VTOC8 label as
found on computers based on
.Tn SPARC64
and
.Tn UltraSPARC.
.Pp
Usage of the
.Ns Nm
utility:
.Pp
.\" ==== ADD ====
.Nm
.Cm add
.Fl t Ar type
.Op Fl a Ar alignment
.Op Fl b Ar start
.Op Fl s Ar size
.Op Fl i Ar index
.Op Fl l Ar label
.Op Fl f Ar flags
.Ar geom
.\" ==== BACKUP ====
.Nm
.Cm backup
.Ar geom
.\" ==== BOOTCODE ====
.Nm
.Cm bootcode
.Op Fl b Ar bootcode
.Op Fl p Ar partcode Fl i Ar index
.Op Fl f Ar flags
.Ar geom
.\" ==== COMMIT ====
.Nm
.Cm commit
.Ar geom
.\" ==== CREATE ====
.Nm
.Cm create
.Fl s Ar scheme
.Op Fl n Ar entries
.Op Fl f Ar flags
.Ar provider
.\" ==== DELETE ====
.Nm
.Cm delete
.Fl i Ar index
.Op Fl f Ar flags
.Ar geom
.\" ==== DESTROY ====
.Nm
.Cm destroy
.Op Fl F
.Op Fl f Ar flags
.Ar geom
.\" ==== MODIFY ====
.Nm
.Cm modify
.Fl i Ar index
.Op Fl l Ar label
.Op Fl t Ar type
.Op Fl f Ar flags
.Ar geom
.\" ==== RECOVER ====
.Nm
.Cm recover
.Op Fl f Ar flags
.Ar geom
.\" ==== RESIZE ====
.Nm
.Cm resize
.Fl i Ar index
.Op Fl a Ar alignment
.Op Fl s Ar size
.Op Fl f Ar flags
.Ar geom
.\" ==== RESTORE ====
.Nm
.Cm restore
.Op Fl lF
.Op Fl f Ar flags
.Ar provider
.Op Ar ...
.\" ==== SET ====
.Nm
.Cm set
.Fl a Ar attrib
.Fl i Ar index
.Op Fl f Ar flags
.Ar geom
.\" ==== SHOW ====
.Nm
.Cm show
.Op Fl l | r
.Op Fl p
.Op Ar geom ...
.\" ==== UNDO ====
.Nm
.Cm undo
.Ar geom
.\" ==== UNSET ====
.Nm
.Cm unset
.Fl a Ar attrib
.Fl i Ar index
.Op Fl f Ar flags
.Ar geom
.\"
.Sh DESCRIPTION
The
.Nm
utility is used to partition GEOM providers, normally disks.
The first argument of which is the action to be taken:
.Bl -tag -width ".Cm bootcode"
.\" ==== ADD ====
.It Cm add
Add a new partition to the partitioning scheme given by
.Ar geom .
The partition begins on the logical block address given by the
.Fl b Ar start
option.
Its size is given by the
.Fl s Ar size
option.
SI unit suffixes are allowed.
One or both
.Fl b
and
.Fl s
options can be omitted.
If so they are automatically calculated.
The type of the partition is given by the
.Fl t Ar type
option.
Partition types are discussed below in the section entitled
.Sx "PARTITION TYPES" .
.Pp
Additional options include:
.Bl -tag -width 12n
.It Fl a Ar alignment
If specified, then
.Nm
utility tries to align
.Ar start
offset and partition
.Ar size
to be multiple of
.Ar alignment
value.
.It Fl i Ar index
The index in the partition table at which the new partition is to be
placed.
The index determines the name of the device special file used
to represent the partition.
.It Fl l Ar label
The label attached to the partition.
This option is only valid when used on partitioning schemes that support
partition labels.
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== BACKUP ====
.It Cm backup
Dump a partition table to standard output in special format used by
.Cm restore
action.
.\" ==== BOOTCODE ====
.It Cm bootcode
Embed bootstrap code into the partitioning scheme's metadata on the
.Ar geom
(using
.Fl b Ar bootcode )
or write bootstrap code into a partition (using
.Fl p Ar partcode
and
.Fl i Ar index ) .
Not all partitioning schemes have embedded bootstrap code, so the
.Fl b Ar bootcode
option is scheme-specific in nature (see the section entitled
.Sx BOOTSTRAPPING
below).
The
.Fl b Ar bootcode
option specifies a file that contains the bootstrap code.
The contents and size of the file are determined by the partitioning
scheme.
The
.Fl p Ar partcode
option specifies a file that contains the bootstrap code intended to be
written to a partition.
The partition is specified by the
.Fl i Ar index
option.
The size of the file must be smaller than the size of the partition.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== COMMIT ====
.It Cm commit
Commit any pending changes for geom
.Ar geom .
All actions are being committed by default and will not result in
pending changes.
Actions can be modified with the
.Fl f Ar flags
option so that they are not being committed by default.
As such, they become pending.
Pending changes are reflected by the geom and the
.Nm
utility, but they are not actually written to disk.
The
.Cm commit
action will write any and all pending changes to disk.
.\" ==== CREATE ====
.It Cm create
Create a new partitioning scheme on a provider given by
.Ar provider .
The
.Fl s Ar scheme
option determines the scheme to use.
The kernel needs to have support for a particular scheme before
that scheme can be used to partition a disk.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl n Ar entries
The number of entries in the partition table.
Every partitioning scheme has a minimum and a maximum number of entries
and this option allows tables to be created with the number of entries
that lies anywhere between the minimum and the maximum.
Some schemes have a maximum equal to the minimum and some schemes have
a maximum large enough to be considered unlimited.
By default, partition tables are created with the minimum number of
entries.
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== DELETE ====
.It Cm delete
Delete a partition from geom
.Ar geom
and further identified by the
.Fl i Ar index
option.
The partition cannot be actively used by the kernel.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== DESTROY ====
.It Cm destroy
Destroy the partitioning scheme as implemented by geom
.Ar geom .
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl F
Forced destroying of the partition table even if it is not empty.
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== MODIFY ====
.It Cm modify
Modify a partition from geom
.Ar geom
and further identified by the
.Fl i Ar index
option.
Only the the type and/or label of the partition can be modified.
To change the type of a partition, specify the new type with the
.Fl t Ar type
option.
To change the label of a partition, specify the new label with the
.Fl l Ar label
option.
Not all partitioning schemes support labels and it is invalid to
try to change a partition label in such cases.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== RECOVER ====
.It Cm recover
Recover corrupt partition's scheme metadata on the geom
.Ar geom .
See the section entitled
.Sx RECOVERING
below for the additional information.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== RESIZE ====
.It Cm resize
Resize a partition from geom
.Ar geom
and further identified by the
.Fl i Ar index
option.
New partition size is expressed in logical block
numbers and can be given by the
.Fl s Ar size
option.
If
.Fl s
option is omitted then new size is automatically calculated
to maximum available from given geom
.Ar geom .
.Pp
Additional options include:
.Bl -tag -width 12n
.It Fl a Ar alignment
If specified, then
.Nm
utility tries to align partition
.Ar size
to be multiple of
.Ar alignment
value.
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== RESTORE ====
.It Cm restore
Restore the partition table from backup previously created by
.Cm backup
action and given from standard input.
Only partition table may be restored.
This action does not affect content of partitions.
This mean that you should copy your data from backup after restoring
partition table and write bootcode again if it is needed.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl F
Destroy partition table on the given
.Ar provider
before doing restore.
.It Fl l
Restore partition labels for partitioning schemes that support them.
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== SET ====
.It Cm set
Set the named attribute on the partition entry.
See the section entitled
.Sx ATTRIBUTES
below for a list of available attributes.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.\" ==== SHOW ====
.It Cm show
Show the current partition information of the specified geoms
or all geoms if none are specified.
Additional options include:
.Bl -tag -width 10n
.It Fl l
For partition schemes that support partition labels print them
instead of partition type.
.It Fl p
Show provider names instead of partition indexes.
.It Fl r
Show raw partition type instead of symbolic name.
.El
.\" ==== UNDO ====
.It Cm undo
Revert any pending changes for geom
.Ar geom .
This action is the opposite of the
.Cm commit
action and can be used to undo any changes that have not been committed.
.\" ==== UNSET ====
.It Cm unset
Clear the named attribute on the partition entry.
See the section entitled
.Sx ATTRIBUTES
below for a list of available attributes.
.Pp
Additional options include:
.Bl -tag -width 10n
.It Fl f Ar flags
Additional operational flags.
See the section entitled
.Sx "OPERATIONAL FLAGS"
below for a discussion
about its use.
.El
.El
.\"
.Sh PARTITION TYPES
Partition types are identified on disk by particular strings or magic
values.
The
.Nm
utility uses symbolic names for common partition types to avoid the
user needing to know these values or other details of the partitioning
scheme in question.
The
.Nm
utility also allows the user to specify scheme-specific partition types
for partition types that do not have symbolic names.
The symbolic names currently understood are:
.Bl -tag -width ".Cm freebsd-vinum"
.It Cm bios-boot
The system partition dedicated to second stage of the boot loader program.
Usually it used by GRUB 2 loader when the partition table is GPT.
The scheme-specific type is
.Qq Li "!21686148-6449-6E6F-744E-656564454649" .
.It Cm efi
The system partition for computers that use the Extensible Firmware
Interface (EFI).
In such cases, the GPT partitioning scheme is being used and the
actual partition type for the system partition can also be specified as
.Qq Li "!c12a7328-f81f-11d2-ba4b-00a0c93ec93ab" .
.It Cm freebsd
A
.Fx
partition that uses the
.Bx
disklabel to sub-divide the
partition into file systems.
This is a legacy partition type and should not be used for the APM
or GPT schemes.
The scheme-specific types are
.Qq Li "!165"
for MBR,
.Qq Li "!FreeBSD"
for APM, and
.Qq Li "!516e7cb4-6ecf-11d6-8ff8-00022d09712b"
for GPT.
.It Cm freebsd-boot
A
.Fx
partition dedicated to bootstrap code.
The scheme-specific type is
.Qq Li "!83bd6b9d-7f41-11dc-be0b-001560b84f0f"
for GPT.
.It Cm freebsd-swap
A
.Fx
partition dedicated to swap space.
The scheme-specific types are
.Qq Li "!FreeBSD-swap"
for APM,
.Qq Li "!516e7cb5-6ecf-11d6-8ff8-00022d09712b"
for GPT, and tag 0x0901 for VTOC8.
.It Cm freebsd-ufs
A
.Fx
partition that contains a UFS or UFS2 file system.
The scheme-specific types are
.Qq Li "!FreeBSD-UFS"
for APM,
.Qq Li "!516e7cb6-6ecf-11d6-8ff8-00022d09712b"
for GPT, and tag 0x0902 for VTOC8.
.It Cm freebsd-vinum
A
.Fx
partition that contains a Vinum volume.
The scheme-specific types are
.Qq Li "!FreeBSD-Vinum"
for APM,
.Qq Li "!516e7cb8-6ecf-11d6-8ff8-00022d09712b"
for GPT, and tag 0x0903 for VTOC8.
.It Cm freebsd-zfs
A
.Fx
partition that contains a ZFS volume.
The scheme-specific types are
.Qq Li "!FreeBSD-ZFS"
for APM,
.Qq Li "!516e7cba-6ecf-11d6-8ff8-00022d09712b"
for GPT, and 0x0904 for VTOC8.
.It Cm mbr
A partition that is sub-partitioned by a master boot record (MBR).
This type is known as
.Qq Li "!024dee41-33e7-11d3-9d69-0008c781f39f"
by GPT.
.El
.Sh ATTRIBUTES
The scheme-specific attributes for EBR:
.Bl -tag -width ".Cm active"
.It Cm active
.El
.Pp
The scheme-specific attributes for GPT:
.Bl -tag -width ".Cm bootfailed"
.It Cm bootme
When set, the
.Nm gptboot
stage 1 boot loader will try to boot the system from this partition.
Multiple partitions might be marked with the
.Cm bootme
attribute.
In such scenario the
.Nm gptboot
will try all
.Cm bootme
partitions one by one, until the next boot stage is successfully entered.
.It Cm bootonce
Setting this attribute automatically sets the
.Cm bootme
attribute.
When set, the
.Nm gptboot
stage 1 boot loader will try to boot the system from this partition only once.
Partitions with both
.Cm bootonce
and
.Cm bootme
attributes are tried before partitions with only the
.Cm bootme
attribute.
Before
.Cm bootonce
partition is tried, the
.Nm gptboot
removes the
.Cm bootme
attribute and tries to execute the next boot stage.
If it fails, the
.Cm bootonce
attribute that is now alone is replaced with the
.Cm bootfailed
attribute.
If the execution of the next boot stage succeeds, but the system is not fully
booted, the
.Nm gptboot
will look for
.Cm bootonce
attributes alone (without the
.Cm bootme
attribute) on the next system boot and will replace those with the
.Cm bootfailed
attribute.
If the system is fully booted, the
.Pa /etc/rc.d/gptboot
start-up script will look for partition with the
.Cm bootonce
attribute alone, will remove the attribute and log that the system was
successfully booted from this partition.
There should be at most one
.Cm bootonce
partition when system is successfully booted.
Multiple partitions might be marked with the
.Cm bootonce
and
.Cm bootme
attribute pairs.
.It Cm bootfailed
This attribute should not be manually managed.
It is managed by the
.Nm gptboot
stage 1 boot loader and the
.Pa /etc/rc.d/gptboot
start-up script.
This attribute is used to mark partitions that had the
.Cm bootonce
attribute set, but we failed to boot from them.
Once we successfully boot, the
.Pa /etc/rc.d/gptboot
script will log all the partitions we failed to boot from and will remove the
.Cm bootfailed
attributes.
.El
.Pp
The scheme-specific attributes for MBR:
.Bl -tag -width ".Cm active"
.It Cm active
.El
.Pp
The scheme-specific attributes for PC98:
.Bl -tag -width ".Cm bootable"
.It Cm active
.It Cm bootable
.El
.Sh BOOTSTRAPPING
.Fx
supports several partitioning schemes and each scheme uses different
bootstrap code.
The bootstrap code is located in the specific disk area for each partitioning
scheme and also it might have different size.
.Pp
The bootstrap code could be separated into two types.
The first one is embedded in the partitioning scheme's metadata, the second
type is located on the specific partition.
The embedding bootstrap code should be done only with the
.Cm gpart bootcode
command with
.Fl b Ar bootcode
option.
The GEOM PART class has knowlege on how to embed bootstrap code into specific
partitioning scheme metadata without damage.
.Pp
The Master Boot Record (MBR) uses 512-bytes bootstrap code image, embedded into
partition table's metadata area.
There are two variants of this bootstrap code:
.Pa /boot/mbr
and
.Pa /boot/boot0 .
The first one searches partition with
.Cm active
attribute (see the
.Sx ATTRIBUTES
section) in the partition table.
Then it runs next bootstrap stage.
The
.Pa /boot/boot0
image contains a boot manager with some additional interactive functions.
.Pp
The BSD disklabel is usually created on top of the MBR partition (slice)
with type
.Cm freebsd
(see the
.Sx "PARTITION TYPES"
section).
It uses 8 KB size bootstrap code image
.Pa /boot/boot ,
embedded into partition table's metadata area.
.Pp
Both types of bootstrap code are used to boot from the GUID Partition Table.
First of all, a protective MBR is embedded into first disk sector from the
.Pa /boot/pmbr
image.
It searches the
.Cm freebsd-boot
partition (see the
.Sx "PARTITION TYPES"
section) in the GPT and runs next bootstrap stage from it.
The
.Cm freebsd-boot
partition should be smaller than 545 KB.
There are two variants of bootstrap code to write to this partition:
.Pa /boot/gptboot
and
.Pa /boot/gptzfsboot .
The first one is used to boot from UFS.
It searches in the GPT partition with type
.Cm freebsd-ufs ,
and it runs the third bootstrap stage (
.Pa /boot/loader )
if it is found.
The
.Pa /boot/gptzfsboot
is used to boot from ZFS.
It searches partition with type
.Cm freebsd-zfs
and starts
.Pa /boot/zfsloader
from it.
.Pp
The VTOC8 scheme does not support embedding bootstrap code.
Instead, the 8 KBytes bootstrap code image
.Pa /boot/boot1
should be written with
.Cm gpart bootcode
command with
.Fl p Ar bootcode
option to all sufficiently large VTOC8 partitions.
To do this the
.Fl i Ar index
option could be ommited.
.Pp
The APM scheme also does not support embedding bootstrap code.
Instead, the 800 KBytes bootstrap code image
.Pa /boot/boot1.hfs
should be written with
.Cm gpart bootcode
command to a partition of type
.Cm freebsd-boot ,
which should also be 800 KB in size.
.Sh OPERATIONAL FLAGS
Actions other than the
.Cm commit
and
.Cm undo
actions take an optional
.Fl f Ar flags
option.
This option is used to specify action-specific operational flags.
By default, the
.Nm
utility defines the
.Ql C
flag so that the action is immediately
committed.
The user can specify
.Dq Fl f Cm x
to have the action result in a pending change that can later, with
other pending changes, be committed as a single compound change with
the
.Cm commit
action or reverted with the
.Cm undo
action.
.Sh RECOVERING
The GEOM PART class supports recovering of partition tables only for GPT.
The GUID partition table has a primary and secondary (backup) copy of
metadata for redundance, these are stored at the begining and the end
of the device respectively.
As a result of having two copies, it is acceptable to have some corruption
within the metadata that is not fatal to the working of GPT.
When the kernel detects corrupt metadata it marks this table as corrupt and
reports the corruption.
Any operations on corrupt tables are prohibited except for
.Cm destroy
and
.Cm recover .
.Pp
If the first sector of a provider is corrupt, the kernel can not detect GPT
even if partition table itself is not corrupt.
You can rewrite the protective MBR using the
.Xr dd 1
command, to restore the ability to detect the GPT.
The copy of the protective MBR is usually located in the
.Pa /boot/pmbr
file.
.Pp
If one GPT header appears to be corrupt but the other copy remains intact,
the kernel will log the following:
.Bd -literal -offset indent
GEOM: provider: the primary GPT table is corrupt or invalid.
GEOM: provider: using the secondary instead -- recovery strongly advised.
.Ed
.Pp
or
.Bd -literal -offset indent
GEOM: provider: the secondary GPT table is corrupt or invalid.
GEOM: provider: using the primary only -- recovery suggested.
.Ed
.Pp
Also
.Nm
commands such as
.Cm show , status
and
.Cm list
will report about corrupt tables.
.Pp
If the size of the device has changed (e.g.\& volume expansion) the
secondary GPT header will no longer be located in the last sector.
This is not a metadata corruption, but it is dangerous because any
corruption of the primary GPT will lead to loss of partition table.
This problem is reported by the kernel with the message:
.Bd -literal -offset indent
GEOM: provider: the secondary GPT header is not in the last LBA.
.Ed
.Pp
This situation can be recovered with the
.Cm recover
command.
This command reconstructs the corrupt metadata using known valid
metadata and relocates the secondary GPT to the end of the device.
.Pp
.Em NOTE :
The GEOM PART class can detect the same partition table visible through
different GEOM providers, and some of them will be marked as corrupt.
Be careful when choosing a provider for recovery.
If you choose incorrectly you can destroy the metadata of another GEOM class,
e.g.\& GEOM MIRROR or GEOM LABEL.
.Sh SYSCTL VARIABLES
The following
.Xr sysctl 8
variables can be used to control the behavior of the
.Nm PART
GEOM class.
The default value is shown next to each variable.
.Bl -tag -width indent
.It Va kern.geom.part.check_integrity : No 1
This variable controls the behaviour of metadata integrity checks.
When integrity checks are enabled, the
.Nm PART
GEOM class verifies all generic partition parameters obtained from the
disk metadata.
If some inconsistency is detected, the partition table will be
rejected with a diagnostic message:
.Sy "GEOM_PART: Integrity check failed (provider, scheme)" .
.El
.Sh EXIT STATUS
Exit status is 0 on success, and 1 if the command fails.
.Sh EXAMPLES
Create GPT scheme on
.Pa ad0 :
.Bd -literal -offset indent
/sbin/gpart create -s GPT ad0
.Ed
.Pp
Embed GPT bootstrap code into protective MBR:
.Bd -literal -offset indent
/sbin/gpart bootcode -b /boot/pmbr ad0
.Ed
.Pp
Create a dedicated
.Cm freebsd-boot
partition that can boot
.Fx
from a
.Cm freebsd-ufs
partition, and install bootstrap code into it.
This partition must be larger than
.Pa /boot/gptboot ,
or the GPT boot you are planning to write, but smaller than 545 KB.
A size of 15 blocks (7680 bytes) would be sufficient for
booting from UFS but let's use 128 blocks (64 KB) here in
this example, in order to reserve some space for potential
future need (e.g.\& from a ZFS partition).
.Bd -literal -offset indent
/sbin/gpart add -b 34 -s 128 -t freebsd-boot ad0
/sbin/gpart bootcode -p /boot/gptboot -i 1 ad0
.Ed
.Pp
Create a 512MB-sized
.Cm freebsd-ufs
partition that would contain UFS where the system boots from:
.Bd -literal -offset indent
/sbin/gpart add -b 162 -s 1048576 -t freebsd-ufs ad0
.Ed
.Pp
Create MBR scheme on
.Pa ada0 ,
then create 30GB-sized
.Fx
slice, mark it active and
install
.Nm boot0
boot manager:
.Bd -literal -offset indent
/sbin/gpart create -s MBR ada0
/sbin/gpart add -t freebsd -s 30G ada0
/sbin/gpart set -a active -i 1 ada0
/sbin/gpart bootcode -b /boot/boot0 ada0
.Ed
.Pp
Now create
.Bx
scheme
.Pf ( Bx
label) with ability to have up to 20 partitions:
.Bd -literal -offset indent
/sbin/gpart create -s BSD -n 20 ada0s1
.Ed
.Pp
Create 1GB-sized UFS partition and 4GB-sized swap partition:
.Bd -literal -offset indent
/sbin/gpart add -t freebsd-ufs -s 1G ada0s1
/sbin/gpart add -t freebsd-swap -s 4G ada0s1
.Ed
.Pp
Install bootstrap code for the
.Bx
label:
.Bd -literal -offset indent
/sbin/gpart bootcode -b /boot/boot ada0s1
.Ed
.Pp
Create VTOC8 scheme on
.Pa da0 :
.Bd -literal -offset indent
/sbin/gpart create -s VTOC8 da0
.Ed
.Pp
Create a 512MB-sized
.Cm freebsd-ufs
partition that would contain UFS where the system boots from:
.Bd -literal -offset indent
/sbin/gpart add -s 512M -t freebsd-ufs da0
.Ed
.Pp
Create a 15GB-sized
.Cm freebsd-ufs
partition that would contain UFS and aligned on 4KB boundaries:
.Bd -literal -offset indent
/sbin/gpart add -s 15G -t freebsd-ufs -a 4k da0
.Ed
.Pp
After having created all required partitions, embed bootstrap code into them:
.Bd -literal -offset indent
/sbin/gpart bootcode -p /boot/boot1 da0
.Ed
.Pp
Create backup of partition table from
.Pa da0 :
.Bd -literal -offset indent
/sbin/gpart backup da0 > da0.backup
.Ed
.Pp
Restore partition table from backup to
.Pa da0 :
.Bd -literal -offset indent
/sbin/gpart restore -l da0 < /mnt/da0.backup
.Ed
.Pp
Clone partition table from
.Pa ada0
to
.Pa ada1
and
.Pa ada2 :
.Bd -literal -offset indent
/sbin/gpart backup ada0 | /sbin/gpart restore -F ada1 ada2
.Ed
.Sh SEE ALSO
.Xr dd 1 ,
.Xr geom 4 ,
.Xr boot0cfg 8 ,
.Xr geom 8
.Sh HISTORY
The
.Nm
utility appeared in
.Fx 7.0 .
.Sh AUTHORS
.An Marcel Moolenaar Aq marcel@FreeBSD.org