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fdisk(1M)		System Administration Commands		     fdisk(1M)

NAME
       fdisk - create or modify	fixed disk partition table

SYNOPSIS
       fdisk [-o offset] [-s size] [-P fill_patt] [-S geom_file] [-w | -r | -d
       | -n | -I | -B |	-t | -T	| -g | -G | -R | -E]  [--F fdisk_file] [  [-v]
       -W  {  fdisk_file  |  -}]  [-h] [-b masterboot] [ -A id : act : bhead :
       bsect : bcyl : ehead : esect : ecyl : rsect : numsect] [	-D id :	act  :
       bhead: bsect : bcyl : ehead: esect : ecyl : rsect : numsect] rdevice

DESCRIPTION
       This command is used to do the following:

	 o  Create and modify an fdisk partition table on x86 systems

	 o  Create  and	 modify	an fdisk partition table on removable media on
	    SPARC or x86 systems

	 o  Install the	master boot record that	is put in the first sector  of
	    the	fixed disk on x86 systems only

       This  table is used by the first-stage bootstrap	(or firmware) to iden-
       tify parts of the disk reserved for different operating systems,	and to
       identify	 the  partition	containing the second-stage bootstrap (the ac-
       tive Solaris partition).	The rdevice argument must be used  to  specify
       the   raw   device   associated	with  the  fixed  disk,	 for  example,
       /dev/rdsk/c0t0d0p0.

       The program can operate in three	different modes. The first is interac-
       tive  mode. In interactive mode,	the program displays the partition ta-
       ble as it exists	on the disk, and then presents	a  menu	 allowing  the
       user to modify the table. The menu, questions, warnings,	and error mes-
       sages are intended to be	self-explanatory.

       In interactive mode, if there is	no partition table on  the  disk,  the
       user  is	given the options of creating a	default	partitioning or	speci-
       fying the initial table values. The default partitioning	allocates  the
       entire  disk for	the Solaris system and makes the Solaris system	parti-
       tion active. In either case, when the initial table is  created,	 fdisk
       also  writes  out  the first-stage bootstrap (x86 only) code along with
       the partition table.

       The second mode of operation is used for	automated entry	addition,  en-
       try  deletion,  or replacement of the entire fdisk table. This mode can
       add or delete an	entry described	on the command line. In	this mode  the
       entire  fdisk  table  can be read in from a file	replacing the original
       table. fdisk can	also be	used to	create this file. There	is  a  command
       line  option  that will cause fdisk to replace any fdisk	table with the
       default of the whole disk for the Solaris system.

       The third mode of operation is used for disk diagnostics. In this mode,
       a  section of the disk can be filled with a user	specified pattern, and
       mode sections of	the disk can also be read or written.

   Menu	Options
       The menu	options	for interactive	mode given by the fdisk	program	are:

       Create a	partition

	   This	option allows the user to create a new partition. The  maximum
	   number of partitions	is 4. The program will ask for the type	of the
	   partition (SOLARIS, MS-DOS, UNIX, or	other).	It will	then  ask  for
	   the size of the partition as	a percentage of	the disk. The user may
	   also	enter the letter c at this point, in which  case  the  program
	   will	ask for	the starting cylinder number and size of the partition
	   in cylinders. If a c	is not entered,	the program will determine the
	   starting  cylinder  number  where the partition will	fit. In	either
	   case, if the	partition would	overlap	an existing partition or  will
	   not	fit,  a	 message  is  displayed	and the	program	returns	to the
	   original menu.

       Change Active (Boot from) partition

	   This	option allows the user to  specify  the	 partition  where  the
	   first-stage	bootstrap  will	 look  for the second-stage bootstrap,
	   otherwise known as the active partition.

       Delete a	partition

	   This	option allows the user to delete a previously  created	parti-
	   tion. Note that this	will destroy all data in that partition.

       Change between Solaris and Solaris2 Partition IDs

	   This	option allows the user to switch between the current fdisk op-
	   erating system partition identifier and the previous	one. This does
	   not	affect any data	in the disk partition and is provided for com-
	   patibility with older software.

       Use the following options to include your modifications to  the	parti-
       tion  table at this time	or to cancel the session without modifying the
       table:

       Exit

	   This	option writes the new version of the table created during this
	   session with	fdisk out to the fixed disk, and exits the program.

       Cancel

	   This	option exits without modifying the partition table.

OPTIONS
       The following options apply to fdisk:

       -A id:act:bhead:bsect:bcyl:ehead:esect:ecyl:rsect:numsect

	   Add a partition as described	by the argument	(see the -F option be-
	   low for the format).	Use of this option will	zero out the
	    VTOC on the	Solaris	partition if the fdisk table changes.

       -b master_boot

	   Specify the file master_boot	as the master boot  program.  The  de-
	   fault master	boot program is	/usr/lib/fs/ufs/mboot.

       -B

	   Default to one Solaris partition that uses the whole	disk.

       -d

	   Turn	 on  verbose  debug  mode.  This will cause fdisk to print its
	   state on stderr as it is used. The output from this	option	should
	   not be used with -F.

       -D id:act:bhead:bsect:bcyl:ehead:esect:ecyl:rsect:numsect

	   Delete  a partition as described by the argument (see the -F	option
	   below for the format). Note that the	 argument  must	 be  an	 exact
	   match  or  the  entry  will not be deleted! Use of this option will
	   zero	out the	VTOC on	the  Solaris  partition	 if  the  fdisk	 table
	   changes.

       -E

	   Create an EFI partition that	uses the entire	disk.

       -F fdisk_file

	   Use	fdisk  file fdisk_file to initialize table. Use	of this	option
	   will	zero out the VTOC on the Solaris partition if the fdisk	 table
	   changes.

	   The	fdisk_file  contains up	to four	specification lines. Each line
	   is delimited	by a new-line character	(0fR). If the first  character
	   of  a  line	is  an asterisk	(*), the line is treated as a comment.
	   Each	line is	composed of entries that are  position-dependent,  are
	   separated by	``white	space''	or colons, and have the	following for-
	   mat:

	   id act bhead	bsect bcyl ehead esect ecyl rsect numsect

	   where the entries have the following	values:

	   id		   This	is the type of partition and the  correct  nu-
			   meric values	may be found in	fdisk.h.

	   act		   This	 is the	active partition flag; 0 means not ac-
			   tive	and 128	means active.

	   bhead	   This	is the head where  the	partition  starts.  If
			   this	is set to 0, fdisk will	correctly fill this in
			   from	other information.

	   bsect	   This	is the sector where the	partition  starts.  If
			   this	is set to 0, fdisk will	correctly fill this in
			   from	other information.

	   bcyl		   This	is the cylinder	where the partition starts. If
			   this	is set to 0, fdisk will	correctly fill this in
			   from	other information.

	   ehead	   This	is the head where the partition	ends. If  this
			   is set to 0,	fdisk will correctly fill this in from
			   other information.

	   esect	   This	is the sector where  the  partition  ends.  If
			   this	is set to 0, fdisk will	correctly fill this in
			   from	other information.

	   ecyl		   This	is the cylinder	where the partition  ends.  If
			   this	is set to 0, fdisk will	correctly fill this in
			   from	other information.

	   rsect	   The relative	sector from the	beginning of the  disk
			   where  the partition	starts.	This must be specified
			   and can be used by fdisk to fill in other fields.

	   numsect	   The size in sectors of this	disk  partition.  This
			   must	 be specified and can be used by fdisk to fill
			   in other fields.

       -g

	   Get the label geometry for disk and display on stdout (see  the  -S
	   option for the format).

       -G

	   Get	the  physical geometry for disk	and display on stdout (see the
	   -S option for the format).

       -h

	   Issue verbose message; message will list all	options	and supply  an
	   explanation for each.

       -I

	   Forgo  device checks. This is used to generate a file image of what
	   would go on a disk without using the	device.	Note that you must use
	   -S with this	option (see above).

       -n

	   Don't update	fdisk table unless explicitly specified	by another op-
	   tion. If no other options are used, -n will only write  the	master
	   boot	record to the disk. In addition, note that fdisk will not come
	   up in interactive mode if the -n option is specified.

       -o offset

	   Block offset	from start of disk. This option	is used	 for  -P,  -r,
	   and -w. Zero	is assumed when	this option is not used.

       -P fill_patt

	   Fill	 disk  with pattern fill_patt. fill_patt can be	decimal	or hex
	   and is used as number for constant long word	pattern. If  fill_patt
	   is  #,  then	 pattern  is block # for each block. Pattern is	put in
	   each	block as long words and	fills each block (see -o and -s).

       -r

	   Read	from disk and write to stdout. See -o and  -s,	which  specify
	   the starting	point and size of the operation.

       -R

	   Treat disk as read-only. This is for	testing	purposes.

       -s size

	   Number of blocks to perform operation on (see -o).

       -S geom_file

	   Set	the  label  geometry  to  the  content	of  the	geom_file. The
	   geom_file contains one specification	line. Each line	 is  delimited
	   by  a new-line character (0fR). If the first	character of a line is
	   an asterisk (*), the	line is	treated	as a  comment.	Each  line  is
	   composed  of	 entries that are position-dependent, are separated by
	   white space,	and have the following format:

	   pcyl	ncyl acyl bcyl nheads nsectors sectsiz

	   where the entries have the following	values:

	   pcyl		   This	is the number of physical  cylinders  for  the
			   drive.

	   ncyl		   This	 is  the  number  of  usable cylinders for the
			   drive.

	   acyl		   This	is the number of alt cylinders for the drive.

	   bcyl		   This	is the number  of  offset  cylinders  for  the
			   drive (should be zero).

	   nheads	   The number of heads for this	drive.

	   nsectors	   The number of sectors per track.

	   sectsiz	   The size in bytes of	a sector.

       -t

	   Adjust  incorrect  slice  table entries so that they	will not cross
	   partition table boundaries.

       -T

	   Remove incorrect slice table	 entries  that	span  partition	 table
	   boundaries.

       -v

	   Output  the	HBA (virtual) geometry dimensions. This	option must be
	   used	in conjunction with the	-W flag. This  option  will  work  for
	   platforms which support virtual geometry. (x86 only)

       -w

	   Write to disk and read from stdin. See -o and -s, which specify the
	   starting point and size of the operation.

       -W -

	   Output the disk table to stdout.

       -W fdisk_file

	   Create an fdisk file	fdisk_file from	disk table. This can  be  used
	   with	the -F option below.

FILES
       /dev/rdsk/c0t0d0p0      Raw device associated with the fixed disk.

       /usr/lib/fs/ufs/mboot   Default master boot program.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Architecture		     |x86 and SPARC		   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO
       uname(1), fmthard(1M), prtvtoc(1M), attributes(5)

DIAGNOSTICS
       Most  messages will be self-explanatory.	The following may appear imme-
       diately after starting the program:

       Fdisk: cannot open <device>

	   This	indicates that the device name argument	is not valid.

       Fdisk: unable to	get device parameters for device <device>

	   This	indicates a problem with the configuration of the fixed	 disk,
	   or an error in the fixed disk driver.

       Fdisk: error reading partition table

	   This	 indicates  that  some error occurred when trying initially to
	   read	the fixed disk.	This could be a	problem	with  the  fixed  disk
	   controller or driver, or with the configuration of the fixed	disk.

       Fdisk: error writing boot record

	   This	 indicates  that  some error occurred when trying to write the
	   new partition table out to the fixed	disk. This could be a  problem
	   with	the fixed disk controller, the disk itself, the	driver,	or the
	   configuration of the	fixed disk.

SunOS 5.10			  19 Nov 2004			     fdisk(1M)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | FILES | ATTRIBUTES | SEE ALSO | DIAGNOSTICS

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