Manual page for newfs(1M)
newfs - construct a new UFS file system
SYNOPSIS
newfs
[
-Nv
] [
mkfs-options
]
raw-device
DESCRIPTION
newfs
is a ``friendly'' front-end to the
mkfs.1m
program for making
UFS
file systems on disk partitions.
newfs
calculates the appropriate parameters to use and
calls
mkfs.
raw-device
is the name of a raw special device residing in
/dev/rdsk
(for example,
/dev/rdsk/c0t0d0s6)
on which to create the file system.
If you run
newfs
interactively (that is, standard input is a tty),
newfs
will prompt for confirmation before making the file system.
If the
-N
option is not specified and the inodes of the device are
not randomized,
newfs
will call
fsirand.1m
Note:
You must be super-user to use this command.
OPTIONS
- -N
-
Print out the file system parameters
that would be used in creating the file system
without actually creating the file system.
fsirand.1m
is not called here.
- -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 blocks per cylinder (SCSI
devices only) to reserve for bad block replacement.
The default is
0.
- -b bsize
-
The logical block size of the file system in bytes (either
4096 or 8192).
The default is
8192.
- -c cgize
-
The number of cylinders per cylinder group (ranging from
1 to 32). The default is
16.
- -d gap
-
Rotational delay. The expected time (in milliseconds)
to service a transfer completion
interrupt and initiate a new transfer on the same disk.
It is used to decide how much rotational spacing to place between
successive blocks in a file. This parameter
can be subsequently changed using the
tunefs.1m
command. The default is disk-type dependent.
- -f fragsize
-
The smallest amount of disk space in bytes
to allocate to a file. The values must
be a power of two selected from the range 512 to the logical
block size.
If logical block size is 4096, legal values are 512, 1024, 2048 and 4096;
if logical block size is 8192, 8192 is also a legal value.
The default is
1024.
- -i nbpi
-
The number of bytes per inode. This specifies the density
of inodes in the file system.
The number is divided into the total size of the file
system to determine the fixed number of inodes to create.
It 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
is
2048.
- -m free
-
The minimum percentage of free space to maintain in the
file system. This space is off-limits to normal users.
Once the file system is filled to this threshold, only
the super-user can continue writing to the file system.
This parameter can be subsequently changed
using the
tunefs.1m
command. The default is
10%.
- -n nrpos
-
The number of different rotational
positions in which
to divide a cylinder group. The default is
8.
- -o opt
-
(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 minimum free space threshold (as specified
by the
-m
option) is less than 10%, space optimization
will be used.
- -r rpm
-
The speed of the disk in revolutions per minute.
The default is
3600.
- -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 cylinders on the disk.
The default is taken from the disk label.
- -C maxcontig
-
The maximum number of blocks, belonging to one file, that will be
allocated contiguously before inserting a rotational delay.
For a 4K file system, the default is
14;
for an 8K file system, the default is
7.
This parameter can be subsequently changed using the
tunefs.1m
command.
Note:
This parameter also controls
clustering. Regardless of the value of
gap,
clustering is enabled only when
maxcontig
is greater than 1.
Clustering allows higher I/O rates for sequential
I/O and is described in
tunefs.1m
EXAMPLES
The following example verbosely displays the parameters
for the raw special device,
c0t0d0s6,
but 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#
SEE ALSO
fsck.1m
fsck_ufs.1m
fsirand.1m
mkfs.1m
mkfs_ufs.1m
tunefs.1m
fs_ufs.4
DIAGNOSTICS
- newfs: special No such file or directory
-
The device specified does not exist, or a disk partition was not
specified.
- special: cannot open
-
You must be super-user to use this command.
Created by unroff & hp-tools.
© by Hans-Peter Bischof. All Rights Reserved (1997).
Last modified 21/April/97
