1.\" Copyright (c) 1983, 1987, 1991, 1993, 1994 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)newfs.8 8.6 (Berkeley) 5/3/95 29.\" $FreeBSD$ 30.\" 31.Dd June 22, 2011 32.Dt NEWFS 8 33.Os 34.Sh NAME 35.Nm newfs 36.Nd construct a new UFS1/UFS2 file system 37.Sh SYNOPSIS 38.Nm 39.Op Fl EJNUjlnt 40.Op Fl L Ar volname 41.Op Fl O Ar filesystem-type 42.Op Fl S Ar sector-size 43.Op Fl T Ar disktype 44.Op Fl a Ar maxcontig 45.Op Fl b Ar block-size 46.Op Fl c Ar blocks-per-cylinder-group 47.Op Fl d Ar max-extent-size 48.Op Fl e Ar maxbpg 49.Op Fl f Ar frag-size 50.Op Fl g Ar avgfilesize 51.Op Fl h Ar avgfpdir 52.Op Fl i Ar bytes 53.Op Fl k Ar held-for-metadata-blocks 54.Op Fl m Ar free-space 55.Op Fl o Ar optimization 56.Op Fl p Ar partition 57.Op Fl r Ar reserved 58.Op Fl s Ar size 59.Ar special 60.Sh DESCRIPTION 61The 62.Nm 63utility is used to initialize and clear file systems before first use. 64The 65.Nm 66utility builds a file system on the specified special file. 67(We often refer to the 68.Dq special file 69as the 70.Dq disk , 71although the special file need not be a physical disk. 72In fact, it need not even be special.) 73Typically the defaults are reasonable, however 74.Nm 75has numerous options to allow the defaults to be selectively overridden. 76.Pp 77The following options define the general layout policies: 78.Bl -tag -width indent 79.It Fl E 80Erase the content of the disk before making the filesystem. 81The reserved area in front of the superblock (for bootcode) will not be erased. 82.Pp 83This option is only relevant for flash based storage devices that use 84wear-leveling algorithms. 85.Pp 86Erasing may take a long time as it writes to every sector on the disk. 87.It Fl J 88Enable journaling on the new file system via gjournal. 89See 90.Xr gjournal 8 91for details. 92.It Fl L Ar volname 93Add a volume label to the new file system. 94.It Fl N 95Cause the file system parameters to be printed out 96without really creating the file system. 97.It Fl O Ar filesystem-type 98Use 1 to specify that a UFS1 format file system be built; 99use 2 to specify that a UFS2 format file system be built. 100The default format is UFS2. 101.It Fl T Ar disktype 102For backward compatibility. 103.It Fl U 104Enable soft updates on the new file system. 105.It Fl a Ar maxcontig 106Specify the maximum number of contiguous blocks that will be 107laid out before forcing a rotational delay. 108The default value is 16. 109See 110.Xr tunefs 8 111for more details on how to set this option. 112.It Fl b Ar block-size 113The block size of the file system, in bytes. 114It must be a power of 2. 115The 116default size is 32768 bytes, and the smallest allowable size is 4096 bytes. 117The optimal block:fragment ratio is 8:1. 118Other ratios are possible, but are not recommended, 119and may produce poor results. 120.It Fl c Ar blocks-per-cylinder-group 121The number of blocks per cylinder group in a file system. 122The default is to compute the maximum allowed by the other parameters. 123This value is 124dependent on a number of other parameters, in particular the block size 125and the number of bytes per inode. 126.It Fl d Ar max-extent-size 127The file system may choose to store large files using extents. 128This parameter specifies the largest extent size that may be used. 129The default value is the file system blocksize. 130It is presently limited to a maximum value of 16 times the 131file system blocksize and a minimum value of the file system blocksize. 132.It Fl e Ar maxbpg 133Indicate the maximum number of blocks any single file can 134allocate out of a cylinder group before it is forced to begin 135allocating blocks from another cylinder group. 136The default is about one quarter of the total blocks in a cylinder group. 137See 138.Xr tunefs 8 139for more details on how to set this option. 140.It Fl f Ar frag-size 141The fragment size of the file system in bytes. 142It must be a power of two 143ranging in value between 144.Ar blocksize Ns /8 145and 146.Ar blocksize . 147The default is 4096 bytes. 148.It Fl g Ar avgfilesize 149The expected average file size for the file system. 150.It Fl h Ar avgfpdir 151The expected average number of files per directory on the file system. 152.It Fl i Ar bytes 153Specify the density of inodes in the file system. 154The default is to create an inode for every 155.Pq 4 * Ar frag-size 156bytes of data space. 157If fewer inodes are desired, a larger number should be used; 158to create more inodes a smaller number should be given. 159One inode is required for each distinct file, so this value effectively 160specifies the average file size on the file system. 161.It Fl j 162Enable soft updates journaling on the new file system. 163This flag is implemented by running the 164.Xr tunefs 8 165utility found in the user's 166.Dv $PATH . 167.It Fl k Ar held-for-metadata-blocks 168Set the amount of space to be held for metadata blocks in each cylinder group. 169When set, the file system preference routines will try to save 170the specified amount of space immediately following the inode blocks 171in each cylinder group for use by metadata blocks. 172Clustering the metadata blocks speeds up random file access 173and decreases the running time of 174.Xr fsck 8 . 175By default 176.Xr newfs 8 177sets it to half of the space reserved to minfree. 178.It Fl l 179Enable multilabel MAC on the new file system. 180.It Fl m Ar free-space 181The percentage of space reserved from normal users; the minimum free 182space threshold. 183The default value used is 184defined by 185.Dv MINFREE 186from 187.In ufs/ffs/fs.h , 188currently 8%. 189See 190.Xr tunefs 8 191for more details on how to set this option. 192.It Fl n 193Do not create a 194.Pa .snap 195directory on the new file system. 196The resulting file system will not support snapshot generation, so 197.Xr dump 8 198in live mode and background 199.Xr fsck 8 200will not function properly. 201The traditional 202.Xr fsck 8 203and offline 204.Xr dump 8 205will work on the file system. 206This option is intended primarily for memory or vnode-backed file systems that 207do not require 208.Xr dump 8 209or 210.Xr fsck 8 211support. 212.It Fl o Ar optimization 213.Cm ( space 214or 215.Cm time ) . 216The file system can either be instructed to try to minimize the time spent 217allocating blocks, or to try to minimize the space fragmentation on the disk. 218If the value of minfree (see above) is less than 8%, 219the default is to optimize for 220.Cm space ; 221if the value of minfree is greater than or equal to 8%, 222the default is to optimize for 223.Cm time . 224See 225.Xr tunefs 8 226for more details on how to set this option. 227.It Fl p Ar partition 228The partition name (a..h) you want to use in case the underlying image 229is a file, so you do not have access to individual partitions through the 230filesystem. 231Can also be used with a device, e.g. 232.Nm 233.Fl p Ar f 234.Ar /dev/da1s3 235is equivalent to 236.Nm 237.Ar /dev/da1s3f . 238.It Fl r Ar reserved 239The size, in sectors, of reserved space 240at the end of the partition specified in 241.Ar special . 242This space will not be occupied by the file system; 243it can be used by other consumers such as 244.Xr geom 4 . 245Defaults to 0. 246.It Fl s Ar size 247The size of the file system in sectors. 248This value defaults to the size of the 249raw partition specified in 250.Ar special 251less the 252.Ar reserved 253space at its end (see 254.Fl r ) . 255A 256.Ar size 257of 0 can also be used to choose the default value. 258A valid 259.Ar size 260value cannot be larger than the default one, 261which means that the file system cannot extend into the reserved space. 262.It Fl t 263Turn on the TRIM enable flag. 264If enabled, and if the underlying device supports the BIO_DELETE 265command, the file system will send a delete request to the underlying 266device for each freed block. 267The trim enable flag is typically set when the underlying device 268uses flash-memory as the device can use the delete command to 269pre-zero or at least avoid copying blocks that have been deleted. 270.El 271.Pp 272The following options override the standard sizes for the disk geometry. 273Their default values are taken from the disk label. 274Changing these defaults is useful only when using 275.Nm 276to build a file system whose raw image will eventually be used on a 277different type of disk than the one on which it is initially created 278(for example on a write-once disk). 279Note that changing any of these values from their defaults will make 280it impossible for 281.Xr fsck 8 282to find the alternate superblocks if the standard superblock is lost. 283.Bl -tag -width indent 284.It Fl S Ar sector-size 285The size of a sector in bytes (almost never anything but 512). 286.El 287.Sh EXAMPLES 288.Dl newfs /dev/ad3s1a 289.Pp 290Creates a new ufs file system on 291.Pa ad3s1a . 292The 293.Nm 294utility will use a block size of 32768 bytes, a fragment size of 4096 bytes 295and the largest possible number of blocks per cylinders group. 296These values tend to produce better performance for most applications 297than the historical defaults 298(8192 byte block size and 1024 byte fragment size). 299This large fragment size may lead to much wasted space 300on file systems that contain many small files. 301.Sh SEE ALSO 302.Xr fdformat 1 , 303.Xr geom 4 , 304.Xr disktab 5 , 305.Xr fs 5 , 306.Xr bsdlabel 8 , 307.Xr camcontrol 8 , 308.Xr dump 8 , 309.Xr dumpfs 8 , 310.Xr fsck 8 , 311.Xr gjournal 8 , 312.Xr growfs 8 , 313.Xr makefs 8 , 314.Xr mount 8 , 315.Xr tunefs 8 , 316.Xr gvinum 8 317.Rs 318.%A M. McKusick 319.%A W. Joy 320.%A S. Leffler 321.%A R. Fabry 322.%T A Fast File System for UNIX 323.%J ACM Transactions on Computer Systems 2 324.%V 3 325.%P pp 181-197 326.%D August 1984 327.%O (reprinted in the BSD System Manager's Manual) 328.Re 329.Sh HISTORY 330The 331.Nm 332utility appeared in 333.Bx 4.2 . 334