NEWFS

Section: Maintenance Commands (8)
Updated: May 21, 1986
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NAME

newfs - construct a new file system

SYNOPSIS

/usr/etc/newfs [ -N ] [ -v ] [ -n ] [ mkfs-options ] character-device [ disk-type ]

DESCRIPTION

Newfs is a ``friendly'' front-end to the mkfs(8) program. Newfs will look up the type of disk a file system is being created on by using the information contained in the disk label of the character-device. If the disk-type argument is specified the information in the disk description file /etc/disktab is used. This disk information is used to calculate the appropriate parameters to use in calling mkfs, then build the file system by forking mkfs and, if the file system is a root partition, install the necessary bootstrap programs in the initial 8 sectors of the device. The -n option prevents the bootstrap programs from being installed. The -N option causes the file system parameters to be printed out without actually creating the file system.

If the -v option is supplied, newfs will print out its actions, including the parameters passed to mkfs.

Options which may be used to override default parameters passed to mkfs are:

-s size: The size of the file system in sectors.
-b block-size: The block size of the file system in bytes.
-f frag-size: The fragment size of the file system in bytes.
-t #tracks/cylinder
-c #cylinders/group: The number of cylinders per cylinder group in a file system. The default value used is 16.
-m free space %: The percentage of space reserved from normal users; the minimum free space threshold. The default value used is 10%.
-o optimization preference (``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 10%, the default is to optimize for space; if the value of minfree greater than or equal to 10%, the default is to optimize for time.
-r revolutions/minute: The speed of the disk in revolutions per minute (normally 3600).
-S sector-size: The size of a sector in bytes.
-i number of bytes per inode: This specifies the density of inodes in the file system. The default is to create an inode for each 2048 bytes of data space. If fewer inodes are desired, a larger number should be used; to create more inodes a smaller number should be given.

FILES

/etc/disktab   for disk geometry and file system partition information

/usr/etc/mkfs  to actually build the file system

/usr/standalone/boot   for boot strapping programs