GPART(8)		  BSD System Manager's Manual		      GPART(8)

NAME
     gpart -- control utility for the disk partitioning GEOM class

SYNOPSIS
     To add support for the disk partitioning GEOM class, place one or more of
     the following lines in your kernel configuration file:

	   options GEOM_PART_APM
	   options GEOM_PART_BSD
	   options GEOM_PART_GPT
	   options GEOM_PART_MBR
	   options GEOM_PART_PC98
	   options GEOM_PART_VTOC8

     The GEOM_PART_APM option adds support for the Apple Partition Map (APM)
     found on Apple Macintosh computers.  The GEOM_PART_BSD option adds sup-
     port for the traditional BSD disklabel.  The GEOM_PART_GPT option adds
     support for the GUID Partition Table (GPT) found on Intel Itanium comput-
     ers and Intel-based Macintosh computers.  The GEOM_PART_MBR option adds
     support for the Master Boot Record (MBR) found on PCs and used on many
     removable media.  The GEOM_PART_PC98 option adds support for the MBR
     variant as used on NEC PC-98 computers.  The GEOM_PART_VTOC8 option adds
     support for Sun's SMI VTOC8 label as found on UltraSPARC-based computers.

     Usage of the gpart(8) utility:

     gpart add -b start -s size -t type [-i index] [-l label] [-f flags] geom
     gpart bootcode [-b bootcode] [-p partcode -i index] [-f flags] geom
     gpart commit geom
     gpart create -s scheme [-n entries] [-f flags] provider
     gpart delete -i index [-f flags] geom
     gpart destroy [-f flags] geom
     gpart modify -i index [-l label] [-t type] [-f flags] geom
     gpart set -a attrib -i index [-f flags] geom
     gpart show [geom ...]
     gpart undo geom
     gpart unset -a attrib -i index [-f flags] geom

DESCRIPTION
     The gpart utility is used to partition GEOM providers, normally disks.
     The first argument of which is the action to be taken:

     add      Add a new partition to the partitioning scheme given by geom.
	      The partition begins on the logical block address given by the
	      -b start option.	Its size is expressed in logical block numbers
	      and given by the -s size option.	The type of the partition is
	      given by the -t type option.  Partition types are discussed in
	      the section entitled "Partition Types".

	      Addition options include:

	      -i 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.

	      -l label	   The label attached to the partition.  This option
			   is only valid when used on partitioning schemes
			   that support partition labels.

	      -f flags	   Additional operational flags.  See the section
			   entitled "Operational flags" below for a discussion
			   about its use.

     bootcode
	      Embed bootstrap code into the partitioning scheme's metadata on
	      the geom (using -b bootcode) or write bootstrap code into a par-
	      tition (using -p partcode and -i index).	Not all partitioning
	      schemes have embedded bootstrap code, so the -b bootcode option
	      is scheme-specific in nature.  For the GPT scheme, embedded
	      bootstrap code is supported.  The bootstrap code is embedded in
	      the protective MBR rather than the GPT.  The -b bootcode option
	      specifies a file that contains the bootstrap code.  The contents
	      and size of the file are determined by the partitioning scheme.
	      For the MBR scheme, it's a 512 byte file of which the first 446
	      bytes are installed as bootstrap code.  The -p partcode option
	      specifies a file that contains the bootstrap code intended to be
	      written to a partition.  The partition is specified by the -i
	      index option.  The size of the file must be smaller than the
	      size of the partition.

	      Addition options include:

	      -f flags	  Additional operational flags.  See the section enti-
			  tled "Operational flags" below for a discussion
			  about its use.

     commit   Commit any pending changes for geom geom.  All actions are being
	      committed by default and will not result in pending changes.
	      Actions can be modified with the -f flags option so that they
	      are not being committed by default.  As such, they become pend-
	      ing.  Pending changes are reflected by the geom and the gpart
	      utility, but they are not actually written to disk.  The commit
	      action will write any and all pending changes to disk.

     create   Create a new partitioning scheme on a provider given by
	      provider.  The -s 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.

	      Addition options include:

	      -n entries  The number of entries in the partition table.  Every
			  partitioning scheme has a minimum and a maximum num-
			  ber of entries and this option allows tables to be
			  created with the number of entries that lies any-
			  where 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.

	      -f flags	  Additional operational flags.  See the section enti-
			  tled "Operational flags" below for a discussion
			  about its use.

     delete   Delete a partition from geom geom and further identified by the
	      -i index option.	The partition cannot be actively used by the
	      kernel.

	      Addition options include:

	      -f flags	  Additional operational flags.  See the section enti-
			  tled "Operational flags" below for a discussion
			  about its use.

     destroy  Destroy the partitioning scheme as implemented by geom geom.

	      Addition options include:

	      -f flags	  Additional operational flags.  See the section enti-
			  tled "Operational flags" below for a discussion
			  about its use.

     modify   Modify a partition from geom geom and further identified by the
	      -i index option.	Only the the type and/or label of the parti-
	      tion can be modified.  To change the type of a partition, spec-
	      ify the new type with the -t type option.  To change the label
	      of a partition, specify the new label with the -l label option.
	      Not all partitioning schemes support labels and it is invalid to
	      try to change a partition label in such cases.

	      Addition options include:

	      -f flags	  Additional operational flags.  See the section enti-
			  tled "Operational flags" below for a discussion
			  about its use.

     set      Set the named attribute on the partition entry.

	      Addition options include:

	      -f flags	  Additional operational flags.  See the section enti-
			  tled "Operational flags" below for a discussion
			  about its use.

     show     Show the current partition information of the specified geoms or
	      all geoms if none are specified.

     undo     Revert any pending changes.  This action is the opposite of the
	      commit action and can be used to undo any changes that have not
	      been committed.

     unset    Clear the named attribute on the partition entry.

	      Addition options include:

	      -f flags	  Additional operational flags.  See the section enti-
			  tled "Operational flags" below for a discussion
			  about its use.

PARTITION TYPES
     The gpart utility uses symbolic names for common partition types to avoid
     that the user needs to know what the partitioning scheme in question is
     and what the actual number or identification needs to be used for a par-
     ticular type.  the gpart utility also allows the user to specify scheme-
     specific partition types for partition types that don't have symbol
     names.  The symbolic names currently understood are:

     efi	    The system partition for computers that use the Extensible
		    Firmware Interface (EFI).  In such cases, the GPT parti-
		    tioning scheme is being used and the actual partition type
		    for the system partition can also be specified as
		    "!c12a7328-f81f-11d2-ba4b-00a0c93ec93ab".

     freebsd	    A FreeBSD partition that uses the BSD 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 "!165" for MBR,
		    "!FreeBSD" for APM, and
		    "!516e7cb4-6ecf-11d6-8ff8-00022d09712b" for GPT.

     freebsd-boot   A FreeBSD partition dedicated to bootstrap code.  The
		    scheme-specific type is "!83bd6b9d-7f41-11dc-
		    be0b-001560b84f0f" for GPT.

     freebsd-swap   A FreeBSD partition dedicated to swap space.  The scheme-
		    specific types are "!FreeBSD-swap" for APM, and
		    "!516e7cb5-6ecf-11d6-8ff8-00022d09712b" for GPT.

     freebsd-ufs    A FreeBSD partition that contains a UFS or UFS2 file sys-
		    tem.  the scheme-specific types are "!FreeBSD-UFS" for
		    APM, and "!516e7cb6-6ecf-11d6-8ff8-00022d09712b" for GPT.

     freebsd-vinum  A FreeBSD partition that contains a Vinum volume.  The
		    scheme-specific types are "!FreeBSD-Vinum" for APM, and
		    "!516e7cb8-6ecf-11d6-8ff8-00022d09712b" for GPT.

     freebsd-zfs    A FreeBSD partition that contains a ZFS volume.  The
		    scheme-specific types are "!FreeBSD-ZFS" for APM, and
		    "!516e7cba-6ecf-11d6-8ff8-00022d09712b" for GPT.

     mbr	    A partition that is sub-partitioned by a master boot
		    record (MBR).  This type is known as
		    "!024dee41-33e7-11d3-9d69-0008c781f39f" by GPT.

OPERATIONAL FLAGS
     Actions other than the commit and undo actions take an optional -f flags
     option.  This option is used to specify action-specific operational
     flags.  By default, the gpart utility defines the 'C' flag so that the
     action is immediately committed.  The user can specify -f 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 commit action
     or reverted with the undo action.

EXIT STATUS
     Exit status is 0 on success, and 1 if the command fails.

EXAMPLES
     Create GPT scheme on ad0.

	   /sbin/gpart create -s GPT ad0

     Embed GPT bootstrap code into protective MBR.

	   /sbin/gpart bootcode -b /boot/pmbr ad0

     Create a dedicated freebsd-boot partition that can boot FreeBSD from a
     freebsd-ufs partition, and install bootstrap code into it.  This parti-
     tion must be larger than /boot/gptboot, or the GPT boot you are planning
     to write.	A size of 15 blocks (7680 bytes) would be sufficient for boot-
     ing from UFS but lets 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).

	   /sbin/gpart add -b 34 -s 128 -t freebsd-boot ad0
	   /sbin/gpart bootcode -p /boot/gptboot -i 1 ad0

     Create a 512MB-sized freebsd-ufs partition that would contain UFS where
     the system boot from.

	   /sbin/gpart add -b 162 -s 1048576 -t freebsd-ufs ad0

SEE ALSO
     geom(4), geom(8),

HISTORY
     The gpart utility appeared in FreeBSD 7.0.

AUTHORS
     Marcel Moolenaar 

BSD				 Nov 18, 2008				   BSD