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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]  [-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 create	and modify the partition table,	and to
       install the master boot (IA only) record	that is	put  in	the first sec-
       tor  of	the  fixed disk.  This table is	used by	the  first-stage boot-
       strap (or firmware) to identify parts of	the disk reserved for  differ-
       ent  operating  systems,	 and to	identify the partition	containing the
       second-stage bootstrap (the active Solaris partition).  The rdevice ar-
       gument  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
       messages	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 (IA 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	 maxi-
	     mum  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  ex-
	     isting  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.

       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 pro-
	     gram.

       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
	     below 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  op-
	     tion  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 ta-
	     ble changes.

       -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 ta-
	     ble changes.

	     The fdisk_file contains up	to four	specification lines. Each line
	     is	delimited by a new-line	character (\n).	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
	     format:

	     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 numeric val-
		   ues may be found in fdisk.h.

	     act   This	is the active partition	flag; 0	means not  active  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 informa-
		   tion.

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

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

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

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

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

	     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
	     option. If	no other options are used, -n will only	write the mas-
	     ter  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 spec-
	     ify 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 (\n). 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. (IA only)

       -w    Write to disk and read from stdin.	  See  -o and  -s, which spec-
	     ify 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		     |IA			   |
       +-----------------------------+-----------------------------+
       |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 prob-
	     lem with the fixed	disk controller, the disk itself, the  driver,
	     or	the configuration of the fixed disk.

SunOS 5.9			  15 Jun 1999			     fdisk(1M)

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

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