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 January 21, 2005 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 EJNUln 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 m Ar free-space 54.Op Fl o Ar optimization 55.Op Fl r Ar reserved 56.Op Fl s Ar size 57.Ar special 58.Sh DESCRIPTION 59The 60.Nm 61utility is used to initialize and clear file systems before first use. 62The 63.Nm 64utility builds a file system on the specified special file. 65(We often refer to the 66.Dq special file 67as the 68.Dq disk , 69although the special file need not be a physical disk. 70In fact, it need not even be special.) 71Typically the defaults are reasonable, however 72.Nm 73has numerous options to allow the defaults to be selectively overridden. 74.Pp 75The following options define the general layout policies: 76.Bl -tag -width indent 77.It Fl E 78Erase the content of the disk before making the filesystem. 79The reserved area in front of the superblock (for bootcode) will not be erased. 80 81This is a relevant option for flash based storage devices that use 82wear levelling algorithms. 83 84NB: Erasing may take as long time as writing every sector on the disk. 85.It Fl J 86Enable journaling on the new file system via gjournal. 87.It Fl L Ar volname 88Add a volume label to the new file system. 89.It Fl N 90Cause the file system parameters to be printed out 91without really creating the file system. 92.It Fl O Ar filesystem-type 93Use 1 to specify that a UFS1 format file system be built; 94use 2 to specify that a UFS2 format file system be built. 95The default format is UFS2. 96.It Fl T Ar disktype 97For backward compatibility. 98.It Fl U 99Enable soft updates on the new file system. 100.It Fl a Ar maxcontig 101Specify the maximum number of contiguous blocks that will be 102laid out before forcing a rotational delay. 103The default value is 16. 104See 105.Xr tunefs 8 106for more details on how to set this option. 107.It Fl b Ar block-size 108The block size of the file system, in bytes. 109It must be a power of 2. 110The 111default size is 16384 bytes, and the smallest allowable size is 4096 bytes. 112The optimal block:fragment ratio is 8:1. 113Other ratios are possible, but are not recommended, 114and may produce poor results. 115.It Fl c Ar blocks-per-cylinder-group 116The number of blocks per cylinder group in a file system. 117The default is to compute the maximum allowed by the other parameters. 118This value is 119dependent on a number of other parameters, in particular the block size 120and the number of bytes per inode. 121.It Fl d Ar max-extent-size 122The file system may choose to store large files using extents. 123This parameter specifies the largest extent size that may be used. 124It is presently limited to its default value which is 16 times 125the file system blocksize. 126.It Fl e Ar maxbpg 127Indicate the maximum number of blocks any single file can 128allocate out of a cylinder group before it is forced to begin 129allocating blocks from another cylinder group. 130The default is about one quarter of the total blocks in a cylinder group. 131See 132.Xr tunefs 8 133for more details on how to set this option. 134.It Fl f Ar frag-size 135The fragment size of the file system in bytes. 136It must be a power of two 137ranging in value between 138.Ar blocksize Ns /8 139and 140.Ar blocksize . 141The default is 2048 bytes. 142.It Fl g Ar avgfilesize 143The expected average file size for the file system. 144.It Fl h Ar avgfpdir 145The expected average number of files per directory on the file system. 146.It Fl i Ar bytes 147Specify the density of inodes in the file system. 148The default is to create an inode for every 149.Pq 4 * Ar frag-size 150bytes of data space. 151If fewer inodes are desired, a larger number should be used; 152to create more inodes a smaller number should be given. 153One inode is required for each distinct file, so this value effectively 154specifies the average file size on the file system. 155.It Fl l 156Enable multilabel MAC on the new file system. 157.It Fl m Ar free-space 158The percentage of space reserved from normal users; the minimum free 159space threshold. 160The default value used is 161defined by 162.Dv MINFREE 163from 164.In ufs/ffs/fs.h , 165currently 8%. 166See 167.Xr tunefs 8 168for more details on how to set this option. 169.It Fl n 170Do not create a 171.Pa .snap 172directory on the new file system. 173The resulting file system will not support snapshot generation, so 174.Xr dump 8 175in live mode and background 176.Xr fsck 8 177will not function properly. 178The traditional 179.Xr fsck 8 180and offline 181.Xr dump 8 182will work on the file system. 183This option is intended primarily for memory or vnode-backed file systems that 184do not require 185.Xr dump 8 186or 187.Xr fsck 8 188support. 189.It Fl o Ar optimization 190.Cm ( space 191or 192.Cm time ) . 193The file system can either be instructed to try to minimize the time spent 194allocating blocks, or to try to minimize the space fragmentation on the disk. 195If the value of minfree (see above) is less than 8%, 196the default is to optimize for 197.Cm space ; 198if the value of minfree is greater than or equal to 8%, 199the default is to optimize for 200.Cm time . 201See 202.Xr tunefs 8 203for more details on how to set this option. 204.It Fl r Ar reserved 205The size, in sectors, of reserved space 206at the end of the partition specified in 207.Ar special . 208This space will not be occupied by the file system; 209it can be used by other consumers such as 210.Xr geom 4 . 211Defaults to 0. 212.It Fl s Ar size 213The size of the file system in sectors. 214This value defaults to the size of the 215raw partition specified in 216.Ar special 217less the 218.Ar reserved 219space at its end (see 220.Fl r ) . 221A 222.Ar size 223of 0 can also be used to choose the default value. 224A valid 225.Ar size 226value cannot be larger than the default one, 227which means that the file system cannot extend into the reserved space. 228.El 229.Pp 230The following options override the standard sizes for the disk geometry. 231Their default values are taken from the disk label. 232Changing these defaults is useful only when using 233.Nm 234to build a file system whose raw image will eventually be used on a 235different type of disk than the one on which it is initially created 236(for example on a write-once disk). 237Note that changing any of these values from their defaults will make 238it impossible for 239.Xr fsck 8 240to find the alternate superblocks if the standard superblock is lost. 241.Bl -tag -width indent 242.It Fl S Ar sector-size 243The size of a sector in bytes (almost never anything but 512). 244.El 245.Sh EXAMPLES 246.Dl newfs /dev/ad3s1a 247.Pp 248Creates a new ufs file system on 249.Pa ad3s1a . 250The 251.Nm 252utility will use a block size of 16384 bytes, a fragment size of 2048 bytes 253and the largest possible number of blocks per cylinders group. 254These values tend to produce better performance for most applications 255than the historical defaults 256(8192 byte block size and 1024 byte fragment size). 257This large fragment size may lead to much wasted space 258on file systems that contain many small files. 259.Sh SEE ALSO 260.Xr fdformat 1 , 261.Xr geom 4 , 262.Xr disktab 5 , 263.Xr fs 5 , 264.Xr bsdlabel 8 , 265.Xr camcontrol 8 , 266.Xr dump 8 , 267.Xr dumpfs 8 , 268.Xr fsck 8 , 269.Xr mount 8 , 270.Xr tunefs 8 , 271.Xr vinum 8 272.Rs 273.%A M. McKusick 274.%A W. Joy 275.%A S. Leffler 276.%A R. Fabry 277.%T A Fast File System for UNIX 278.%J ACM Transactions on Computer Systems 2 279.%V 3 280.%P pp 181-197 281.%D August 1984 282.%O (reprinted in the BSD System Manager's Manual) 283.Re 284.Sh HISTORY 285The 286.Nm 287utility appeared in 288.Bx 4.2 . 289