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newfs(1M)		System Administration Commands		     newfs(1M)

       newfs - construct a UFS file system

       newfs [-NTv] [mkfs-options] raw-device

       newfs  is a "friendly" front-end	to the mkfs(1M)	program	for making UFS
       file systems on disk partitions.	newfs calculates the  appropriate  pa-
       rameters	to use and calls mkfs.

       If  run interactively (that is, standard	input is a tty), newfs prompts
       for confirmation	before making the file system.

       If the -N option	is not specified and the inodes	of the device are  not
       randomized, newfs calls fsirand(1M).

       You must	be super-user or have appropriate write	privileges to use this
       command,	except when creating a UFS file	system on a diskette. See  EX-

   Creating a Multiterabyte UFS	File System
       Keep  the  following  limitations in mind when creating a multiterabyte
       UFS file	system:

	 o  nbpi is set	to 1 Mbyte unless you specifically set it higher.  You
	    cannot  set	 nbpi  lower  than 1 Mbyte on a	multiterabyte UFS file

	 o  fragsize is	set equal to bsize.

       The following options are supported:

       -N	       Print out the file system parameters that would be used
		       to create the file system without actually creating the
		       file system. fsirand(1M)	is not called here.

       -T	       Set the parameters of the file system to	allow eventual
		       growth  to  over	 a terabyte in total file system size.
		       This option sets	fragsize to be the same	as bsize,  and
		       sets  nbpi  to 1	Mbyte, unless the -i option is used to
		       make it even larger.  If	you use	the -f or  -i  options
		       to specify a fragsize or	nbpi that is incompatible with
		       this option, the	user-supplied  value  of  fragsize  or
		       nbpi is ignored.

       -v	       Verbose.	 newfs	prints	out its	actions, including the
		       parameters passed to mkfs.

       mkfs-options    Options that override the default parameters are:

		       -a apc	       The number  of  alternate  sectors  per
				       cylinder	 to  reserve for bad block re-
				       placement for SCSI  devices  only.  The
				       default is 0.

				       This option is not applicable for disks
				       with EFI	labels and is ignored.

		       -b bsize	       The logical block size of the file sys-
				       tem  in bytes, either 4096 or 8192. The
				       default is 8192.	The sun4u architecture
				       does not	support	the 4096 block size.

		       -c cgsize       The  number  of	cylinders per cylinder
				       group, ranging from 16 to 256. The  de-
				       fault  is  calculated  by  dividing the
				       number of sectors in the	file system by
				       the  number  of	sectors	in a gigabyte.
				       Then, the result	is multiplied  by  32.
				       The  default value is always between 16
				       and 256.

				       mkfs  can  override  this  value.   See
				       mkfs_ufs(1M) for	details.

				       This option is not applicable for disks
				       with EFI	labels and is ignored.

		       -C maxcontig    The maximum number of  logical  blocks,
				       belonging  to  one file,	that are allo-
				       cated contiguously. The default is cal-
				       culated as follows:

				       maxcontig = disk	drive maximum transfer size / disk block size

				       If  the	disk  drive's maximum transfer
				       size cannot be determined, the  default
				       value  for maxcontig is calculated from
				       kernel parameters as follows:

				       If maxphys is less than ufs_maxmaxphys,
				       which  is  typically 1 Mbyte, then max-
				       contig is set  to  maxphys.  Otherwise,
				       maxcontig is set	to ufs_maxmaxphys.

				       You  can	 set maxcontig to any positive
				       integer value.

				       The actual value	will be	the lesser  of
				       what  has  been	specified and what the
				       hardware	supports.

				       You can subsequently change this	param-
				       eter by using tunefs(1M).

		       -d gap	       Rotational  delay. This option is obso-
				       lete in the  Solaris  10	 release.  The
				       value is	always set to 0, regardless of
				       the input value.

		       -f fragsize     The smallest amount of  disk  space  in
				       bytes  that can be allocated to a file.
				       fragsize	must be	a power	of  2  divisor
				       of bsize, where:

				       bsize / fragsize	is 1, 2, 4, or 8.

				       This  means  that  if the logical block
				       size is 4096, legal values for fragsize
				       are 512,	1024, 2048, and	4096. When the
				       logical block size is 8192, legal  val-
				       ues are 1024, 2048, 4096, and 8192. The
				       default value is	1024.

				       For file	systems	greater	 than  1  ter-
				       abyte  or for file systems created with
				       the -T option, fragsize	is  forced  to
				       match block size	(bsize).

		       -i nbpi	       The  number  of	bytes per inode, which
				       specifies the density of	inodes in  the
				       file system. The	number is divided into
				       the total size of the  file  system  to
				       determine  the number of	inodes to cre-

				       This value should reflect the  expected
				       average	size of	files in the file sys-
				       tem. If fewer  inodes  are  desired,  a
				       larger  number should be	used.  To cre-
				       ate  more  inodes,  a  smaller	number
				       should  be  given. The default for nbpi
				       is as follows:

				       Disk size		 Density

				       Less than 1GB		 2048
				       Less than 2GB		 4096
				       Less than 3GB		 6144
				       3GB to 1	Tbyte		 8192
				       Greater than 1 Tbyte
					  or created with -T	 1048576

				       The number of inodes  can  increase  if
				       the  file  system  is expanded with the
				       growfs command.

		       -m free	       The minimum percentage of free space to
				       maintain	in the file system, between 0%
				       and 99%,	 inclusively.  This  space  is
				       off-limits  to  users.	Once  the file
				       system is  filled  to  this  threshold,
				       only  the super-user can	continue writ-
				       ing to the file system.

				       The default  is	((64  Mbytes/partition
				       size) * 100), rounded down to the near-
				       est integer and limited between 1%  and
				       10%, inclusively.

				       This   parameter	 can  be  subsequently
				       changed using the tunefs(1M) command.

		       -n nrpos	       The number of different rotational  po-
				       sitions	in  which to divide a cylinder
				       group. The default is 8.

				       This option is not applicable for disks
				       with EFI	labels and is ignored.

		       -o space|time   The  file  system  can  either  be  in-
				       structed	to try to  minimize  the  time
				       spent  allocating  blocks, or to	try to
				       minimize	the space fragmentation	on the
				       disk. The default is time.

				       This   parameter	 can  subsequently  be
				       changed with the	tunefs(1M) command.

		       -r rpm	       The rotational speed  of	 the  disk  in
				       revolutions per minute.	The default is
				       driver- or device-specific.

				       Note that you specify rpm for newfs and
				       rps for mkfs.

				       This option is not applicable for disks
				       with EFI	labels and is ignored.

		       -s size	       The size	of the file system in sectors.
				       The default is to use the entire	parti-

		       -t ntrack       The number of tracks  per  cylinder  on
				       the disk. The default is	taken from the
				       disk label.

				       This option is not applicable for disks
				       with EFI	labels and is ignored.

       The following operands are supported:

       raw-device      The  name  of a raw special device residing in the /dev
		       directory (for example, /dev/rdsk/c0t0d0s6) on which to
		       create the file system.

       See  largefile(5) for the description of	the behavior of	newfs when en-
       countering files	greater	than or	equal to 2 Gbyte ( 2**31 bytes).

       Example 1: Displaying the Parameters for	the Raw	Special	Device

       The following example verbosely displays	the  parameters	 for  the  raw
       special	device,	 c0t0d0s6. It does not actually	create a new file sys-

       example#	newfs -Nv /dev/rdsk/c0t0d0s6
       mkfs -F ufs -o N	/dev/rdsk/c0t0d0s6 1112940 54 15 8192 1024 16 10 60
       2048 t 0	-1 8 /dev/rdsk/c0t0d0s6: 1112940 sectors in
       1374 cylinders of 15 tracks, 54 sectors 569.8MB in 86 cyl
       groups (16 c/g, 6.64MB/g, 3072 i/g) super-block backups
       (for fsck -b #) at:
       32, 13056, 26080, 39104,	52128, 65152, 78176, 91200, 104224, ...

       Example 2: Creating a UFS File System

       The following example creates a UFS file	system on a diskette  that  is
       managed by Volume Manager.

       example%	newfs /vol/dev/aliases/floppy0
       newfs: construct	a new file system /vol/dev/aliases/floppy0: (y/n)? y
       /vol/dev/aliases/floppy0: 2880 sectors in 80 cylinders of 2 tracks,
       18 sectors 1.4MB	in 5 cyl groups	(16 c/g, 0.28MB/g, 128 i/g)
       super-block backups (for	fsck -F	ufs -o b=#) at:
       32, 640,	1184, 1792, 2336, ...

       Example	3: Creating a UFS File System That Will	Eventually Be Grown to
       a Multiterabyte UFS File	System

       The following example creates a UFS file	system that will eventually be
       grown to	a multiterabyte	UFS file system.

       This   command	creates	  a  800-Gbyte	file  system  on  the  volume,

       # newfs -T /dev/md/rdsk/d99
       newfs: construct	a new file system /dev/md/rdsk/d99: (y/n)? y
	  /dev/md/rdsk/d99: 1677754368 sectors in 45512	cylinders of
	  144 tracks, 256 sectors
	  819216.0MB in	1821 cyl groups	(25 c/g, 450.00MB/g, 448 i/g) ...

       Then, if	you increase the volume	size for this file system, you can use
       the  growfs command to expand the file system. The file system is grown
       to 1.2 terabytes	in this	example:

       # growfs	-v /dev/md/rdsk/d99
       /usr/lib/fs/ufs/mkfs -G /dev/md/rdsk/d99	2516631552 /dev/md/rdsk/d99:
	  2516631552 sectors in	68268 cylinders	of 144 tracks, 256  sectors
	  1228824.0MB in 2731 cyl groups (25 c/g, 450.00MB/g, 448 i/g)...

       The following exit values are returned:

       0	The operation was successful.

       1, 10	Usage error or internal	error. A message is output  to	STDERR
		explaining the error.

       Other  exit  values  may	 be  returned  by mkfs(1M), which is called by

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

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Availability		     |SUNWcsu			   |

       fsck(1M),   fsck_ufs(1M),    fsirand(1M),    mkfs(1M),	 mkfs_ufs(1M),
       tunefs(1M), attributes(5), largefile(5),	ufs(7FS)

       newfs: No such file or directory	       The  device  specified does not
					       exist, or a disk	partition  was
					       not specified.

       special:	cannot open		       You  must  write	 access	to the
					       device to use this command.

SunOS 5.10			  6 Nov	2003			     newfs(1M)


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