NAME

       mkfs.nilfs2 - create a NILFS2 filesystem

SYNOPSIS

       mkfs  -t  nilfs2  [  -b  block-size  ] [ -B blocks-per-segment ] [ -c ] [ -f ] [ -K ] [ -L
       volume-label ] [ -m reserved-segments-percentage ] [ -n ] [ -O feature[,...]  ] [ -h  ]  [
       -q ] [ -v ] [ -V ] device

       mkfs.nilfs2  [ -b block-size ] [ -B blocks-per-segment ] [ -c ] [ -f ] [ -K ] [ -L volume-
       label ] [ -m reserved-segments-percentage ] [ -n ] [ -O feature[,...]  ] [ -h ] [ -q  ]  [
       -v ] [ -V ] device

DESCRIPTION

       mkfs.nilfs2  is  used to create a nilfs2 filesystem (usually in a disk partition).  device
       is the special file corresponding to the device (e.g.  /dev/sdXX). Usually mkfs.nilfs2  is
       invoked from the mkfs(8) front-end program.

       The exit code returned by mkfs.nilfs2 is 0 on success and 1 on failure.

OPTIONS

       -b block-size
              Specify  the  size  of  blocks in bytes.  The valid block size is 1024, 2048, 4096,
              8192 bytes, ..., and the maximum block size is restricted to the system page  size.
              For most machines, it is 4096 bytes.  The default block size is 4096 bytes.

       -B blocks-per-segment
              Specify  the  number  of  blocks  in a segment, where the segment (also called full
              segment) is an allocation unit of disk space of NILFS.  This  parameter  gives  the
              size  of  segment  and consequently determines how many segments are aligned in the
              specified device.  The default number of blocks per segment is 2048 (= 8MB with 4KB
              blocks).

       -c     Check the device for bad blocks before building the filesystem.

       -f     Force overwrite when an existing filesystem is detected on the device.  By default,
              mkfs.nilfs2 will not write  to  the  device  if  it  suspects   that   there  is  a
              filesystem on the device already.

       -h     Display help message and exit.

       -K     Keep, do not attempt to discard blocks at mkfs time (discarding blocks initially is
              useful on solid state drives and sparse / thinly-provisioned storage).

       -L new-volume-label
              Set the volume label for the filesystem to new-volume-label.  The maximum length of
              the volume label is 80 bytes.

       -m reserved-segments-percentage
              Specify  the  percentage  of  the  segments  reserved  for garbage collection.  The
              default percentage is 5%.

       -n     Cause mkfs.nilfs2 to not actually create a filesystem, but display what it would be
              do if it were to create a filesystem.

       -O feature[,...]
              Create  a  filesystem  with the given features (filesystem options), overriding the
              default filesystem options.

              The filesystem feature set is comprised of a list of features, separated by commas,
              that  are to be enabled.  To disable a feature, simply prefix the feature name with
              a caret ('^') character.  The  pseudo-filesystem  feature  "none"  will  clear  all
              filesystem features.

              block_count
                     Enable block count per checkpoint.

       -q     Quiet execution.  Useful if mkfs.nilfs2 is run in a script.

       -v     Verbose execution.

       -V     Print the version number of mkfs.nilfs2 and exit.

AUTHOR

       This    version    of    mkfs.nilfs2    has    been    written    by    Ryusuke    Konishi
       <konishi.ryusuke@lab.ntt.co.jp>.

AVAILABILITY

       mkfs.nilfs2   is   part   of   the   nilfs-utils   package   and   is    available    from
       http://nilfs.sourceforge.net.

SEE ALSO

       nilfs(8), mkfs(8), badblocks(8).