NEWFS(8) Maintenance Commands and Procedures NEWFS(8)

NAME

newfs - construct a UFS file system

SYNOPSIS

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

DESCRIPTION

newfs is a "friendly" front-end to the mkfs(8) program for making UFS
file systems on disk partitions. newfs calculates the appropriate
parameters 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(8).


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 EXAMPLES.

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 system.

o fragsize is set equal to bsize.

OPTIONS

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(8) is not called here.


-S

Sends to stdout a human-readable version of the superblock that
would be used to create a filesystem with the specified
configuration parameters.


-B

Sends to stdout a binary (machine-readable) version of the
superblock that would be used to create a filesystem with the
specified configuration parameters.


-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 replacement 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 system 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 default 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(8) 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 allocated contiguously. The default is calculated 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 maxcontig 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 parameter by using
tunefs(8).


-d gap

Rotational delay. This option is obsolete 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 values are 1024, 2048,
4096, and 8192. The default value is 1024.

For file systems greater than 1 terabyte 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 create.

This value should reflect the expected average size of files
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 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 writing to the
file system.

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

This parameter can be subsequently changed using the
tunefs(8) command.


-n nrpos

The number of different rotational positions 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 instructed 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(8)
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 partition.


-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.

OPERANDS

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.

USAGE

See largefile(7) for the description of the behavior of newfs when
encountering files greater than or equal to 2 Gbyte ( 2^31 bytes).

EXAMPLES

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
system:


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 a volume manager that makes use of the mount point /vol.


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,
/dev/md/rdsk/d99.


# 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)...

EXIT STATUS

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(8), which is called by
newfs.

SEE ALSO

ufs(4FS), attributes(7), largefile(7), fsck(8), fsck_ufs(8),
fsirand(8), mkfs(8), mkfs_ufs(8), tunefs(8)

DIAGNOSTICS

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.


March 1, 2007 NEWFS(8)