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

NAME
     newfs -- construct	a new file system

SYNOPSIS
     newfs [-FGINZ] [-a	maxcontig] [-B byte-order] [-b block-size]
	   [-d maxbsize] [-e maxbpg] [-f frag-size] [-g	avgfilesize]
	   [-h avgfpdir] [-i bytes-per-inode] [-m free-space] [-n inodes]
	   [-O filesystem-format] [-o optimization] [-q	quota]
	   [-S sector-size] [-s	size] [-T disk-type] [-v volname] [-V verbose]
	   special

DESCRIPTION
     newfs is used to initialize and clear file	systems	before first use.  Be-
     fore running newfs	the disk must be labeled using disklabel(8).  newfs
     builds a file system on the specified special device basing its defaults
     on	the information	in the disk label.  Typically the defaults are reason-
     able, however newfs has numerous options to allow the defaults to be se-
     lectively overridden.

     Options with numeric arguments may	contain	an optional (case-insensitive)
     suffix:
	   b	Bytes; causes no modification.	(Default)
	   k	Kilo; multiply the argument by 1024.
	   m	Mega; multiply the argument by 1048576.
	   g	Giga; multiply the argument by 1073741824.
	   t	Tera; multiply the argument by 1099511627776.

     The following options define the general layout policies.

     -a	maxcontig
		 This sets the obsolete	maxcontig parameter.

     -B	byte-order
		 Specify the metadata byte order of the	file system to be cre-
		 ated.	Valid byte orders are `be' and `le'.  If no byte order
		 is specified, the file	system is created in host byte order.

     -b	block-size
		 The block size	of the file system, in bytes.  It must be a
		 power of two.	The smallest allowable size is 4096 bytes.
		 The default size depends upon the size	of the file system:

		       file system size	 block-size
		       < 20 MB		 4 KB
		       < 1000 MB	 8 KB
		       < 128 GB		 16 KB
		       >= 128 GB	 32 KB

     -d	maxbsize
		 Set the maximum extent	size to	maxbsize.

     -e	maxbpg	 This indicates	the maximum number of blocks any single	file
		 can allocate out of a cylinder	group before it	is forced to
		 begin allocating blocks from another cylinder group.  The de-
		 fault is about	one quarter of the total blocks	in a cylinder
		 group.	 See tunefs(8) for more	details	on how to set this op-
		 tion.

     -F		 Create	a file system image in special.	 The file system size
		 needs to be specified with "-s	size".	No attempts to use or
		 update	the disk label will be made.

     -f	frag-size
		 The fragment size of the file system in bytes.	 It must be a
		 power of two ranging in value between block-size/8 and
		 block-size.  The optimal block-size:frag-size ratio is	8:1.
		 Other ratios are possible, but	are not	recommended, and may
		 produce unpredictable results.	 The default size depends upon
		 the size of the file system:

		       file system size	 frag-size
		       < 20 MB		 0.5 KB
		       < 1000 MB	 1 KB
		       < 128 GB		 2 KB
		       >= 128 GB	 4 KB

     -G		 Treat garbage parameters as non-fatal.	 Using this option may
		 result	in a file system which causes a	kernel panic and
		 should	only be	used for testing.

     -g	avgfilesize
		 The expected average file size	for the	file system.

     -h	avgfpdir
		 The expected average number of	files per directory on the
		 file system.

     -I		 Do not	require	that the file system type listed in the	disk
		 label is `4.2BSD' or `Apple UFS'.

     -i	bytes-per-inode
		 This specifies	the density of inodes in the file system.  If
		 fewer inodes are desired, a larger number should be used; to
		 create	more inodes a smaller number should be given.  The de-
		 fault is to create an inode for every (4 * frag-size) bytes
		 of data space:

		       file system size	 bytes-per-inode
		       < 20 MB		 2 KB
		       < 1000 MB	 4 KB
		       < 128 GB		 8 KB
		       >= 128 GB	 16 KB

     -m	free-space
		 The percentage	of space reserved from normal users; the mini-
		 mum free space	threshold.  The	default	value used is 5%.  See
		 tunefs(8) for more details on how to set this option.

     -N		 Causes	the file system	parameters to be printed out without
		 really	creating the file system.

     -n	inodes	 This specifies	the number of inodes for the filesystem.  If
		 both -i and -n	are specified then -n takes precedence.

     -O	filesystem-format
		 Select	the filesystem-format.
		       0    4.3BSD; This option	is primarily used to build
			    root file systems that can be understood by	older
			    boot ROMs.	This generates an FFSv1	file system
			    with level 1 format.
		       1    FFSv1; normal Fast File System, level 4 format.
			    Also known as `FFS', `UFS',	or `UFS1'.  This is
			    the	default.
		       2    FFSv2; enhanced Fast File System, suited for more
			    than 1 Terabyte capacity.  This is also known as
			    `UFS2'.
		 See fsck_ffs(8) for more information about format levels.

		 To create an LFS filesystem see newfs_lfs(8).	To create a
		 Linux ext2 filesystem see newfs_ext2fs(8).

     -o	optimization
		 Optimization preference; either "space" or "time".  The file
		 system	can either be instructed to try	to minimize the	time
		 spent allocating blocks, or to	try to minimize	the space
		 fragmentation on the disk.  If	the value of minfree (see
		 above)	is less	than 5%, the default is	to optimize for	space;
		 if the	value of minfree is greater than or equal to 5%, the
		 default is to optimize	for time.  See tunefs(8) for more de-
		 tails on how to set this option.

     -q	quota	 enable	a quota.  quota	can be one of user or group to enable
		 the specified quota type.  Multiple -q	can be used to enable
		 all types at once.

     -s	size	 The size of the file system in	sectors.  An `s' suffix	will
		 be interpreted	as the number of sectors (the default).	 All
		 other suffixes	are interpreted	as per other numeric argu-
		 ments,	except that the	number is converted into sectors by
		 dividing by the sector	size (as specified by -S secsize) af-
		 ter suffix interpretation.

		 If no -s size is specified then the filesystem	size defaults
		 to that of the	partition, or, if -F is	specified, the exist-
		 ing file.

		 If size is negative the specified size	is subtracted from the
		 default size (reserving space at the end of the partition).

     -T	disk-type
		 Uses information for the specified disk from /etc/disktab in-
		 stead of trying to get	the information	from the disk label.

     -V	verbose	 This controls the amount of information written to stdout:
		       0    No output.
		       1    Overall size and cylinder group details.
		       2    A progress bar (dots ending	at right hand margin).
		       3    The	first few super-block backup sector numbers
			    are	displayed before the progress bar.
		       4    All	the super-block	backup sector numbers are dis-
			    played (no progress	bar).
		 The default is	3.  If -N is specified newfs stops before out-
		 putting the progress bar.

     -v	volname	 This specifies	that an	Apple UFS filesystem should be created
		 with the given	volume name.

     -Z		 Pre-zeros the file system image created with -F.  This	is
		 necessary if the image	is to be used by vnd(4)	(which doesn't
		 support file systems with `holes').

     The following option overrides the	standard sizes for the disk geometry.
     The default value is taken	from the disk label.  Changing this default is
     useful only when using newfs to build a file system whose raw image will
     eventually	be used	on a different type of disk than the one on which it
     is	initially created (for example on a write-once disk).  Note that
     changing this value from its default will make it impossible for
     fsck_ffs(8) to find the alternative superblocks if	the standard su-
     perblock is lost.

     -S	sector-size
		 The size of a sector in bytes (almost never anything but
		 512).	Defaults to 512.

NOTES
     The file system is	created	with `random' inode generation numbers to im-
     prove NFS security.

     The owner and group IDs of	the root node of the new file system are set
     to	the effective UID and GID of the user initializing the file system.

     For the newfs command to succeed, the disk	label should first be updated
     such that the fstype field	for the	partition is set to `4.2BSD' or	`Apple
     UFS', unless -F or	-I is used.

     To	create and populate a filesystem image within a	file use the makefs(8)
     utility.

     The partition size	is found using fstat(2), not by	inspecting the disk
     label.  The block size and	fragment size will be written back to the disk
     label only	if the last character of special references the	same partition
     as	the minor device number.

     Unless -F is specified, special must be a raw device.  This means that
     for example wd0a or /dev/rwd0a must be specified instead of /dev/wd0a.

SEE ALSO
     fstat(2), disktab(5), fs(5), disklabel(8),	diskpart(8), dumpfs(8),
     fsck_ffs(8), makefs(8), mount(8), mount_mfs(8), newfs_ext2fs(8),
     newfs_lfs(8), newfs_msdos(8), tunefs(8)

     M.	McKusick, W. Joy, S. Leffler, and R. Fabry, "A Fast File System	for
     UNIX,", ACM Transactions on Computer Systems 2, 3,	pp 181-197, August
     1984, (reprinted in the BSD System	Manager's Manual).

     M.	McKusick, "Enhancements	to the fast filesystem to support multi-
     terabyte storage systems",	Proceedings of the BSD Conference 2003,	pp
     79-90, September 2003.

HISTORY
     The newfs command appeared	in 4.2BSD.

BSD				 June 30, 2012				   BSD

NAME | SYNOPSIS | DESCRIPTION | NOTES | SEE ALSO | HISTORY

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