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NEWFS(8)                    System Manager's Manual                   NEWFS(8)



NAME
       newfs - create a new file system

SYNOPSIS
       /usr/etc/newfs [ -Nv ] [ mkfs-options ] raw-special-device

DESCRIPTION
       newfs  is  a  "friendly" front-end to the mkfs(8) program.  On Sun sys-
       tems, the disk type is determined by reading the  disk  label  for  the
       specified raw-special-device.

       raw-special-device  is  the  name  of  a raw special device residing in
       /dev, including the disk partition, where you want the new file  system
       to  be created.  If you want to make a file system on sd0[a-h], specify
       sd0[a-h], rsd0[a-h] or /dev/rsd0[a-h]; if you  only  specify  sd0[a-h],
       newfs will find the proper device.

       newfs  then  calculates  the  appropriate  parameters to use in calling
       mkfs, and builds the file system by forking mkfs.

       You must be super-user to use this command.

OPTIONS
       -N     Print out the file system parameters without  actually  creating
              the file system.

       -v     Verbose.  newfs prints out its actions, including the parameters
              passed to mkfs.

       mkfs-options
              Options that override the default parameters passed  to  mkfs(8)
              are:

              -a apc Number of alternates per cylinder (SCSI devices only).

              -b block-size
                     The  block size of the file system in bytes.  The default
                     is 8192.

              -C maxcontig
                     The maximum number of blocks, belonging to one file, that
                     will  be  allocated contiguously before inserting a rota-
                     tional delay.  The default varies from  drive  to  drive.
                     Drives  without  internal  buffers (or drives/controllers
                     that don't advertise the existence of an internal buffer)
                     default to 1.  Drives with buffers default to 7.

                     This parameter is limited in the following way:

                         blocksize * maxcontig must be <= maxphys

                     maxphys is a read-only kernel variable that specifies the
                     maximum block transfer size (in bytes) that the I/O  sub-
                     system is capable of satisfying.  (This limit is enforced
                     by mount(2), not by newfs or mkfs.)

                     Note: This parameter also controls  clustering.   Regard-
                     less  of   the   value of rotdelay, 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(8).

              -c #cylinders/group
                     The number of cylinders per cylinder group in a file sys-
                     tem.  The default is 16.

              -d rotdelay
                     This  specifies  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 clus-
                     ters/blocks in a file.

              -f frag-size
                     The  fragment  size  of  the  file  system in bytes.  The
                     default is 1024.

              -i bytes/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.

              -m free-space%
                     The percentage of space reserved from normal  users;  the
                     minimum free space threshold.  The default is 10%.

              -o optimization
                     (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 speci-
                     fied  by  the -m option) is less than 10%, the default is
                     to optimize for space; if the minimum free space  thresh-
                     old  is  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  (fre-
                     quently 3600).

              -s size
                     The size of the file system in sectors.

              -t #tracks/cylinder
                     The  number  of  tracks  per  cylinders on the disk.  The
                     default is 16.

              -n #rotational-positions
                     The number of distinguished  rotational  positions.   The
                     default is 8.

EXAMPLES
       The  following  example  verbosely  displays the parameters for the raw
       special device, sd0a, but does not actually create a new file system:

              example%  /usr/etc/newfs -vN sd0a
              mkfs -N /dev/rsd0a 16048 34 8 8192 1024 16 10 60 2048 t 0 -1 8 -1
              /dev/rsd0a:    16048 sectors in 59 cylinders of 8 tracks, 34 sectors
                   8.2Mb in 4 cyl groups (16 c/g, 2.23Mb/g, 896 i/g)
              super-block backups (for fsck -b#) at:
               32, 4432, 8832, 13232,
              example%

SEE ALSO
       fs(5), fsck(8), installboot(8S), mkfs(8), tunefs(8)

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.

NOTES
       To  install  the  bootstrap programs for a root partition, run install-
       boot(8S) after newfs.



                                  5 July 1990                         NEWFS(8)