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SGDISK(8)		       GPT fdisk Manual			     SGDISK(8)

NAME
       sgdisk  - Command-line GUID partition table (GPT) manipulator for Linux
       and Unix

SYNOPSIS
       sgdisk [	options	] device

DESCRIPTION
       GPT fdisk is a text-mode	menu-driven package for	creation and manipula-
       tion  of	 partition  tables. It consists	of two programs: the text-mode
       interactive gdisk and the command-line sgdisk. Either program will  au-
       tomatically convert an old-style	Master Boot Record (MBR) partition ta-
       ble or BSD disklabel stored without an MBR  carrier  partition  to  the
       newer  Globally	Unique Identifier (GUID) Partition Table (GPT) format,
       or will load a GUID partition table. This man page documents  the  com-
       mand-line sgdisk	program.

       Some advanced data manipulation and recovery options require you	to un-
       derstand	the distinctions between the main and backup data, as well  as
       between	the  GPT  headers and the partition tables. For	information on
       MBR vs. GPT, as well as GPT terminology and structure, see the extended
       gdisk   documentation  at  http://www.rodsbooks.com/gdisk/  or  consult
       Wikipedia.

       The sgdisk program employs a user interface that's  based  entirely  on
       the  command  line, making it suitable for use in scripts or by experts
       who want	to make	one or two quick changes to a disk. (The  program  may
       query  the  user	when certain errors are	encountered, though.) The pro-
       gram's name is based on sfdisk, but the user options of	the  two  pro-
       grams are entirely different from one another.

       Ordinarily,  sgdisk  operates on	disk device files, such	as /dev/sda or
       /dev/hda	under Linux,  /dev/disk0  under	 Mac  OS  X,  or  /dev/ad0  or
       /dev/da0	 under	FreeBSD.  The  program	can also operate on disk image
       files, which can	be either copies of whole disks	(made with dd, for in-
       stance)	or  raw	 disk images used by emulators such as QEMU or VMWare.
       Note that only raw disk images are supported;  sgdisk  cannot  work  on
       compressed or other advanced disk image formats.

       The  MBR	partitioning system uses a combination of cylinder/head/sector
       (CHS) addressing	and logical block  addressing  (LBA).  The  former  is
       klunky  and limiting. GPT drops CHS addressing and uses 64-bit LBA mode
       exclusively. Thus, GPT data structures, and therefore  sgdisk,  do  not
       need to deal with CHS geometries	and all	the problems they create.

       For best	results, you should use	an OS-specific partition table program
       whenever	possible. For example, you should make	Mac  OS	 X  partitions
       with  the  Mac  OS X Disk Utility program and Linux partitions with the
       Linux gdisk, sgdisk, or GNU Parted programs.

       Upon start, sgdisk attempts to identify the partition type  in  use  on
       the  disk.  If  it  finds valid GPT data, sgdisk	will use it. If	sgdisk
       finds a valid MBR or BSD	disklabel but no GPT data, it will attempt  to
       convert	the MBR	or disklabel into GPT form. (BSD disklabels are	likely
       to have unusable	first and/or final  partitions	because	 they  overlap
       with  the GPT data structures, though.) GPT fdisk can identify, but not
       use data	in, Apple Partition Map	(APM) disks, which are used on	680x0-
       and  PowerPC-based  Macintoshes.	If you specify any option that results
       in changes to an	MBR or BSD disklabel, sgdisk ignores those changes un-
       less the	-g (--mbrtogpt), -z (--zap), or	-Z (--zap-all) option is used.
       If you use the -g option, sgdisk	replaces the MBR or disklabel  with  a
       GPT.  This  action is potentially dangerous! Your system	may become un-
       bootable, and partition type codes may become  corrupted	 if  the  disk
       uses  unrecognized type codes. Boot problems are	particularly likely if
       you're multi-booting with any GPT-unaware OS.

       The MBR-to-GPT conversion will leave at least one gap in	the  partition
       numbering  if  the original MBR used logical partitions.	These gaps are
       harmless, but you can eliminate them by using the -s  (--sort)  option,
       if  you	like.  (Doing  this  may require you to	update your /etc/fstab
       file.)

       When creating a fresh partition table, certain considerations may be in
       order:

       *      For data (non-boot) disks, and for boot disks used on BIOS-based
	      computers	with GRUB as the boot loader, partitions may  be  cre-
	      ated in whatever order and in whatever sizes are desired.

       *      Boot disks for EFI-based systems require an EFI System Partition
	      (sgdisk internal code 0xEF00) formatted as FAT-32.   The	recom-
	      mended  size  of	this  partition	 is  between  100 and 300 MiB.
	      Boot-related files are stored here. (Note	that GNU Parted	 iden-
	      tifies such partitions as	having the "boot flag" set.)

       *      Some boot	loaders	for BIOS-based systems make use	of a BIOS Boot
	      Partition	(sgdisk	internal code 0xEF02), in which	the  secondary
	      boot  loader  is	stored,	 possibly  without  the	 benefit  of a
	      filesystem. This partition can typically be quite	small (roughly
	      32 to 200	KiB), but you should consult your boot loader documen-
	      tation for details.

       *      If Windows is to boot from a GPT disk, a partition of  type  Mi-
	      crosoft  Reserved	 (sgdisk internal code 0x0C01) is recommended.
	      This partition should be about 128 MiB in	 size.	It  ordinarily
	      follows  the  EFI	 System	Partition and immediately precedes the
	      Windows data partitions. (Note that GNU Parted creates  all  FAT
	      partitions  as this type,	which actually makes the partition un-
	      usable for normal	file storage in	both Windows and Mac OS	X.)

       *      Some OSes' GPT utilities create some blank space (typically  128
	      MiB)  after  each	partition. The intent is to enable future disk
	      utilities	to use this space. Such	free space is not required  of
	      GPT disks, but creating it may help in future disk maintenance.

OPTIONS
       Some  options  take no arguments, others	take one argument (typically a
       partition number), and others take compound arguments with colon	delim-
       itation.	 For instance, -n (--new) takes	a partition number, a starting
       sector  number,	and  an	 ending	 sector	 number,  as  in   sgdisk   -n
       2:2000:50000  /dev/sdc,	which  creates	a  new	partition, numbered 2,
       starting	at sector 2000 an ending at sector 50,000, on /dev/sdc.

       Unrelated options may be	combined; however, some	such combinations will
       be  nonsense  (such  as deleting	a partition and	then changing its GUID
       type code).  sgdisk interprets options in the order  in	which  they're
       entered,	 so  effects can vary depending	on order. For instance,	sgdisk
       -s -d 2 sorts the partition table entries and then deletes partition  2
       from  the  newly-sorted	list;  but sgdisk -d 2 -s deletes the original
       partition 2 and then sorts the modified partition table.

       Error checking and opportunities	to correct mistakes in sgdisk are min-
       imal.  Although	the  program endeavors to keep the GPT data structures
       legal, it does not prompt for verification before  performing  its  ac-
       tions. Unless you require a command-line-driven program,	you should use
       the interactive gdisk instead of	sgdisk,	since gdisk allows you to quit
       without saving your changes, should you make a mistake.

       Although	 sgdisk	 is  based  on the same	partition-manipulation code as
       gdisk, sgdisk implements	fewer features than its	 interactive  sibling.
       Options available in sgdisk are:

       -a, --set-alignment=value
	      Set the sector alignment multiple. GPT fdisk aligns the start of
	      partitions to sectors that are multiples of  this	 value,	 which
	      defaults	to  2048  on  freshly  formatted disks.	This alignment
	      value is necessary to obtain optimum  performance	 with  Western
	      Digital  Advanced	Format and similar drives with larger physical
	      than logical sector sizes, with some types of RAID  arrays,  and
	      with SSD devices.

       -A,	  --attributes=list|[partnum:show|or|nand|xor|=|set|clear|tog-
       gle|get[:bitnum|hexbitmask]]
	      View or set  partition  attributes.  Use	list  to  see  defined
	      (known)  attribute  values.  Omit	the partition number (and even
	      the device filename) when	using this option. The others  require
	      a	 partition  number.  The show and get options show the current
	      attribute	settings (all attributes or for	a particular bit,  re-
	      spectively).  The	 or,  nand, xor, =, set, clear,	and toggle op-
	      tions enable you to change the attribute	bit  value.  The  set,
	      clear,  toggle, and get options work on a	bit number; the	others
	      work on a	hexadecimal bit	mask.  For  example,  type  sgdisk  -A
	      4:set:2  /dev/sdc	 to  set  the  bit  2  attribute  (legacy BIOS
	      bootable)	on partition 4 on /dev/sdc.

       -b, --backup=file
	      Save partition data to a backup file. You	can back up your  cur-
	      rent in-memory partition table to	a disk file using this option.
	      The resulting file is a binary file consisting of	the protective
	      MBR, the main GPT	header,	the backup GPT header, and one copy of
	      the partition table, in that order. Note that the	backup	is  of
	      the current in-memory data structures, so	if you launch the pro-
	      gram, make changes, and then use this option,  the  backup  will
	      reflect  your  changes.  If the GPT data structures are damaged,
	      the backup may not accurately reflect  the  damaged  state;  in-
	      stead,  they  will reflect GPT fdisk's first-pass	interpretation
	      of the GPT.

       -c, --change-name=partnum:name
	      Change the GPT name of a partition. This name is	encoded	 as  a
	      UTF-16  string,  but proper entry	and display of anything	beyond
	      basic ASCII values requires suitable locale  and	font  support.
	      For  the most part, Linux	ignores	the partition name, but	it may
	      be important in some OSes. If you	want to	set a  name  that  in-
	      cludes  a	 space,	enclose	it in quotation	marks, as in sgdisk -c
	      1:"Sample	Name" /dev/sdb.	Note that the GPT name of a  partition
	      is  distinct  from  the filesystem name, which is	encoded	in the
	      filesystem's data	structures.

       -C, --recompute-chs
	      Recompute	CHS values in protective or hybrid  MBR.  This	option
	      can  sometimes  help if a	disk utility, OS, or BIOS doesn't like
	      the CHS values used by the partitions in the protective  or  hy-
	      brid  MBR.  In  particular, the GPT specification	requires a CHS
	      value of 0xFFFFFF	for over-8GiB partitions, but  this  value  is
	      technically  illegal by the usual	standards. Some	BIOSes hang if
	      they encounter this value. This option  will  recompute  a  more
	      normal  CHS value	-- 0xFEFFFF for	over-8GiB partitions, enabling
	      these BIOSes to boot.

       -d, --delete=partnum
	      Delete a partition. This action deletes the entry	from the  par-
	      tition  table  but  does not disturb the data within the sectors
	      originally allocated to the partition on the disk. If  a	corre-
	      sponding hybrid MBR partition exists, gdisk deletes it, as well,
	      and expands any adjacent 0xEE (EFI GPT) MBR protective partition
	      to fill the new free space.

       -D, --display-alignment
	      Display  current sector alignment	value. Partitions will be cre-
	      ated on multiples	of the sector value reported by	 this  option.
	      You can change the alignment value with the -a option.

       e, --move-second-header
	      Move backup GPT data structures to the end of the	disk. Use this
	      option if	you've added disks to a	RAID array,  thus  creating  a
	      virtual  disk with space that follows the	backup GPT data	struc-
	      tures. This command moves	the backup GPT data structures to  the
	      end of the disk, where they belong.

       -E, --end-of-largest
	      Displays	the  sector number of the end of the largest available
	      block of sectors on the disk. A script may store this value  and
	      pass it back as part of -n's option to create a partition. If no
	      unallocated sectors are available,  this	function  returns  the
	      value 0.

       -f, --first-in-largest
	      Displays the sector number of the	start of the largest available
	      block of sectors on the disk. A script may store this value  and
	      pass it back as part of -n's option to create a partition. If no
	      unallocated sectors are available,  this	function  returns  the
	      value  0.	 Note that this	parameter is blind to partition	align-
	      ment; when you actually create  a	 partition,  its  start	 point
	      might be changed from this value.

       -F, --first-aligned-in-largest
	      Similar  to  -f  (--first-in-largest), except returns the	sector
	      number with the current alignment	correction applied.  Use  this
	      function if you need to compute the actual partition start point
	      rather than a theoretical	start point or the actual start	 point
	      if you set the alignment value to	1.

       -g, --mbrtogpt
	      Convert  an MBR or BSD disklabel disk to a GPT disk. As a	safety
	      measure, use of this option is required on MBR or	BSD  disklabel
	      disks  if	 you  intend to	save your changes, in order to prevent
	      accidentally damaging such disks.

       -G, --randomize-guids
	      Randomize	the disk's GUID	and all	partitions' unique GUIDs  (but
	      not  their partition type	code GUIDs). This function may be used
	      after cloning a disk in order to render  all  GUIDs  once	 again
	      unique.

       -h, --hybrid
	      Create  a	hybrid MBR. This option	takes from one to three	parti-
	      tion numbers, separated by colons, as arguments. The created hy-
	      brid  MBR	 places	 an EFI	GPT (type 0xEE)	partition first	in the
	      table, followed by the  partition(s)  you	 specify.  Their  type
	      codes  are  based	on the GPT fdisk type codes divided by 0x0100,
	      which is usually correct for  Windows  partitions.  If  the  ac-
	      tive/bootable flag should	be set,	you must do so in another pro-
	      gram, such as fdisk. The gdisk program offers additional	hybrid
	      MBR creation options.

       -i, --info=partnum
	      Show  detailed  partition	 information.  The summary information
	      produced by the -p command necessarily omits many	details,  such
	      as  the  partition's unique GUID and the translation of sgdisk's
	      internal partition type code to a	plain type name. The -i	option
	      displays this information	for a single partition.

       -l, --load-backup=file
	      Load  partition  data from a backup file.	This option is the re-
	      verse of the -b option. Note that	restoring partition data  from
	      anything	but  the original disk is not recommended. This	option
	      will work	even if	the disk's original partition  table  is  bad;
	      however, most other options on the same command line will	be ig-
	      nored.

       -L, --list-types
	      Display a	summary	of partition types. GPT	uses a GUID  to	 iden-
	      tify  partition types for	particular OSes	and purposes. For ease
	      of data entry, sgdisk compresses these into two-byte (four-digit
	      hexadecimal)  values  that  are  related to their	equivalent MBR
	      codes. Specifically, the MBR code	is multiplied  by  hexadecimal
	      0x0100.  For  instance,  the code	for Linux swap space in	MBR is
	      0x82, and	it's 0x8200 in gdisk. A	one-to-one  correspondence  is
	      impossible, though. Most notably,	the codes for all varieties of
	      FAT and NTFS partition correspond	to a single GPT	code  (entered
	      as 0x0700	in sgdisk). Some OSes use a single MBR code but	employ
	      many more	codes in GPT. For these, sgdisk	adds code numbers  se-
	      quentially,  such	 as 0xa500 for a FreeBSD disklabel, 0xa501 for
	      FreeBSD boot, 0xa502 for FreeBSD swap,  and  so  on.  Note  that
	      these two-byte codes are unique to gdisk and sgdisk. This	option
	      does not require you to specify a	valid disk device filename.

       -m, --gpttombr
	      Convert disk from	GPT to MBR form. This option takes from	one to
	      four partition numbers, separated	by colons, as arguments. Their
	      type codes are based on the GPT  fdisk  type  codes  divided  by
	      0x0100.  If  the active/bootable flag should be set, you must do
	      so in another program, such as fdisk.  The gdisk program	offers
	      additional MBR conversion	options. It is not possible to convert
	      more than	four partitions	from GPT to MBR	 form  or  to  convert
	      partitions  that	start  above  the 2TiB mark or that are	larger
	      than 2TiB.

       -n, --new=partnum:start:end
	      Create a new partition. You enter	a partition  number,  starting
	      sector,  and an ending sector. Both start	and end	sectors	can be
	      specified	in absolute terms as sector numbers  or	 as  positions
	      measured	 in  kibibytes	(K),  mebibytes	 (M),  gibibytes  (G),
	      tebibytes	(T), or	pebibytes (P); for instance, 40M  specifies  a
	      position 40MiB from the start of the disk. You can specify loca-
	      tions relative to	the start or  end  of  the  specified  default
	      range  by	preceding the number by	a '+' or '-' symbol, as	in +2G
	      to specify a point 2GiB after the	default	start sector, or -200M
	      to  specify  a  point 200MiB before the last available sector. A
	      start or end value of 0 specifies	the default  value,  which  is
	      the  start  of  the largest available block for the start	sector
	      and the end of the same block for	 the  end  sector.  A  partnum
	      value  of	0 causes the program to	use the	first available	parti-
	      tion number. Subsequent uses of the -A, -c, -t, and  -u  options
	      may also use 0 to	refer to the same partition.

       -N, --largest-new=num
	      Create a new partition that fills	the largest available block of
	      space on the disk. Note that if used on a	completely blank disk,
	      this  is	likely	to result in a sector-moved warning, since the
	      first available sector (normally 34) doesn't fall	on a 2048-sec-
	      tor  boundary  (the  default  for	alignment). You	can use	the -a
	      (--set-alignment)	option to adjust the alignment,	if desired.  A
	      num  value  of  0	 causes	the program to use the first available
	      partition	number.

       -o, --clear
	      Clear out	all partition data. This includes GPT header data, all
	      partition	 definitions,  and  the	protective MBR.	Note that this
	      operation	will, like most	other operations, fail	on  a  damaged
	      disk.  If	 you want to prepare a disk you	know to	be damaged for
	      GPT use, you should first	wipe it	with -Z	and then partition  it
	      normally.	This option will work even if the disk's original par-
	      tition table is bad; however, most other	options	 on  the  same
	      command line will	be ignored.

       -p, --print
	      Display  basic  partition	 summary data. This includes partition
	      numbers, starting	and ending sector  numbers,  partition	sizes,
	      sgdisk's	partition  types codes,	and partition names. For addi-
	      tional information, use the -i (--info) option.

       -P, --pretend
	      Pretend to make specified	changes. In-memory GPT data structures
	      are  altered  according to other parameters, but changes are not
	      written to disk.

       -r, --transpose
	      Swap two partitions' entries in the partition table. One or both
	      partitions  may be empty,	although swapping two empty partitions
	      is pointless. For	 instance,  if	partitions  1-4	 are  defined,
	      transposing  1 and 5 results in a	table with partitions numbered
	      from 2-5.	Transposing partitions in this way has	no  effect  on
	      their  disk  space allocation; it	only alters their order	in the
	      partition	table.

       -R, --replicate=second_device_filename
	      Replicate	the main device's partition  table  on	the  specified
	      second  device.	Note that the replicated partition table is an
	      exact copy, including all	GUIDs; if the device should  have  its
	      own unique GUIDs,	you should use the -G option on	the new	disk.

       -s, --sort
	      Sort partition entries. GPT partition numbers need not match the
	      order of partitions on the disk. If you want them	to match,  you
	      can use this option.  Note that some partitioning	utilities sort
	      partitions whenever they make changes. Such changes will be  re-
	      flected  in  your	 device	 filenames,  so	 you  may need to edit
	      /etc/fstab if you	use this option.

       -t, --typecode=partnum:{hexcode|GUID}
	      Change a single partition's type code. You enter the  type  code
	      using  either  a	two-byte hexadecimal number, as	described ear-
	      lier,   or   a   fully-specified	  GUID	  value,    such    as
	      EBD0A0A2-B9E5-4433-87C0-68B6B72699C7.

       -T, --transform-bsd=partnum
	      Transform	 BSD partitions	into GPT partitions. This option works
	      on BSD disklabels	held within GPT	(or converted MBR) partitions.
	      Converted	 partitions'  type codes are likely to need manual ad-
	      justment.	sgdisk will attempt to convert BSD  disklabels	stored
	      on the main disk when launched, but this conversion is likely to
	      produce first and/or last	partitions that	are unusable. The many
	      BSD  variants  means that	the probability	of sgdisk being	unable
	      to convert a BSD disklabel is high compared to the likelihood of
	      problems with an MBR conversion.

       -u, --partition-guid=partnum:guid
	      Set  the	partition unique GUID for an individual	partition. The
	      GUID may be a complete GUID or 'R' to set	a random GUID.

       -U, --disk-guid=guid
	      Set the GUID for the disk. The GUID may be a  complete  GUID  or
	      'R' to set a random GUID.

       --usage
	      Print a brief summary of available options.

       -v, --verify
	      Verify  disk. This option	checks for a variety of	problems, such
	      as incorrect CRCs	and mismatched main and	backup data. This  op-
	      tion  does  not automatically correct most problems, though; for
	      that, you	must use options  on  the  recovery  &	transformation
	      menu.  If	no problems are	found, this command displays a summary
	      of unallocated disk space. This option will  work	 even  if  the
	      disk's  original partition table is bad; however,	most other op-
	      tions on the same	command	line will be ignored.

       -V, --version
	      Display program version information. This	 option	 may  be  used
	      without specifying a device filename.

       -z, --zap
	      Zap  (destroy)  the  GPT data structures and then	exit. Use this
	      option if	you want to repartition	a GPT disk using fdisk or some
	      other  GPT-unaware  program.  This  option destroys only the GPT
	      data structures; it leaves the MBR intact. This makes it	useful
	      for  wiping out GPT data structures after	a disk has been	repar-
	      titioned for MBR using a GPT-unaware utility; however, there's a
	      risk  that  it will damage boot loaders or even the start	of the
	      first or end of the last MBR partition. If you use it on a valid
	      GPT  disk,  the  MBR  will be left with an inappropriate EFI GPT
	      (0xEE) partition definition, which you can delete	using  another
	      utility.

       -Z, --zap-all
	      Zap  (destroy)  the  GPT	and MBR	data structures	and then exit.
	      This option works	much like -z, but as it	wipes the MBR as  well
	      as the GPT, it's more suitable if	you want to repartition	a disk
	      after using this option, and completely unsuitable if you've al-
	      ready repartitioned the disk.

       -?, --help
	      Print a summary of options.

RETURN VALUES
       sgdisk returns various values depending on its success or failure:

       0      Normal program execution

       1      Too few arguments

       2      An error occurred	while reading the partition table

       3      Non-GPT disk detected and	no -g option

       4      An error prevented saving	changes

       5      An error occurred	while reading standard input (should never oc-
	      cur with sgdisk, but may with gdisk)

       8      Disk replication operation (-R) failed

BUGS
       As of March 2014	(version 0.8.10), sgdisk  should  be  considered  beta
       software. Known bugs and	limitations include:

       *      The  program  compiles correctly only on Linux, FreeBSD, and Mac
	      OS X. Linux versions for x86-64 (64-bit),	x86 (32-bit), and Pow-
	      erPC  (32-bit)  have been	tested,	with the x86-64	version	having
	      seen the most testing.

       *      The FreeBSD version of the program can't write  changes  to  the
	      partition	 table to a disk when existing partitions on that disk
	      are mounted. (The	same problem exists with  many	other  FreeBSD
	      utilities,  such	as gpt,	fdisk, and dd.)	This limitation	can be
	      overcome by typing sysctl	 kern.geom.debugflags=16  at  a	 shell
	      prompt.

       *      The  fields used to display the start and	end sector numbers for
	      partitions in the	-p option are 14 characters wide. This	trans-
	      lates to a limitation of about 45	PiB. On	larger disks, the dis-
	      played columns will go out of alignment.

       *      The program can load only	up to 128 partitions (4	primary	parti-
	      tions  and 124 logical partitions) when converting from MBR for-
	      mat.  This  limit	 can  be  raised  by  changing	 the   #define
	      MAX_MBR_PARTS line in the	basicmbr.h source code file and	recom-
	      piling;  however,	 such  a   change   will   require   using   a
	      larger-than-normal partition table. (The limit of	128 partitions
	      was chosen because that number equals the	 128  partitions  sup-
	      ported by	the most common	partition table	size.)

       *      Converting  from	MBR format sometimes fails because of insuffi-
	      cient space at the start or (more	commonly) the end of the disk.
	      Resizing	the  partition	table (using the 's' option in the ex-
	      perts' menu) can sometimes overcome this	problem;  however,  in
	      extreme  cases  it  may be necessary to resize a partition using
	      GNU Parted or a similar tool prior to conversion with gdisk.

       *      MBR conversions work only	if the disk has	correct	LBA  partition
	      descriptors.  These  descriptors	should	be present on any disk
	      over 8 GiB in size or on smaller disks partitioned with any  but
	      very ancient software.

       *      BSD  disklabel  support  can create first	and/or last partitions
	      that overlap with	the GPT	data structures. This can sometimes be
	      compensated  by  adjusting  the partition	table size, but	in ex-
	      treme cases the affected partition(s) may	need to	be deleted.

       *      Because of the highly variable nature of	BSD  disklabel	struc-
	      tures,  conversions  from	 this form may be unreliable --	parti-
	      tions may	be dropped, converted in a way that  creates  overlaps
	      with  other partitions, or converted with	incorrect start	or end
	      values. Use this feature with caution!

       *      Booting after converting an MBR or BSD disklabel disk is	likely
	      to  be disrupted.	Sometimes re-installing	a boot loader will fix
	      the problem, but other times you may need	to switch  boot	 load-
	      ers.  Except  on	EFI-based  platforms, Windows through at least
	      Windows 7	RC doesn't support booting from	GPT disks. Creating  a
	      hybrid  MBR  (using the 'h' option on the	recovery & transforma-
	      tion menu) or abandoning GPT in favor of MBR may	be  your  only
	      options in this case.

AUTHORS
       Primary author: Roderick	W. Smith (rodsmith@rodsbooks.com)

       Contributors:

       * Yves Blusseau (1otnwmz02@sneakemail.com)

       * David Hubbard (david.c.hubbard@gmail.com)

       * Justin	Maggard	(justin.maggard@netgear.com)

       * Dwight	Schauer	(dschauer@ti.com)

       * Florian Zumbiehl (florz@florz.de)

SEE ALSO
       bsdlabel(8),  cgdisk(8),	 fdisk(8),  fixparts(8),  gdisk(8),  gpart(8),
       gpt(8), newfs(8)

       http://en.wikipedia.org/wiki/GUID_Partition_Table

       http://developer.apple.com/technotes/tn2006/tn2166.html

       http://www.rodsbooks.com/gdisk/

AVAILABILITY
       The sgdisk command is part of the GPT fdisk package  and	 is  available
       from Rod	Smith.

Roderick W. Smith		    0.8.10			     SGDISK(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | RETURN VALUES | BUGS | AUTHORS | SEE ALSO | AVAILABILITY

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