| NEWFS_EXT2FS(8) | System Manager's Manual | NEWFS_EXT2FS(8) | 
newfs_ext2fs —
| newfs_ext2fs | [ -FINZ] [-bblock-size] [-Dinodesize] [-ffrag-size] [-ibytes-per-inode] [-mfree-space] [-ninodes] [-Ofilesystem-format] [-Ssector-size] [-ssize] [-Vverbose] [-vvolname] special | 
newfs_ext2fs is used to initialize and clear ext2 file
  systems before first use. Before running newfs_ext2fs
  the disk must be labeled using
  disklabel(8).
  newfs_ext2fs builds a file system on the specified
  special device basing its defaults on the information in the disk label.
  Typically the defaults are reasonable, however
  newfs_ext2fs has numerous options to allow the
  defaults to be selectively overridden.
Options with numeric arguments may contain an optional (case-insensitive) suffix:
The following options define the general layout policies.
-b
    block-size-D
    inodesize-F-s
      size”. No attempts to use or update the disk
      label will be made.-f
    frag-size-ILinux Ext2’.-i
    bytes-per-inode-m
    free-space-N-n
    inodes-i and -n are specified
      then -n takes precedence. The default number of
      inodes is calculated from a number of blocks in the file system.-O
    filesystem-formatGOOD_OLD_REV’; this option is
          primarily used to build root file systems that can be understood by
          old or dumb firmwares for bootstrap.DYNAMIC_REV’; the default.
          Various extended (and sometimes incompatible) features are enabled
          (though not all features are supported on
          NetBSD). Currently only the following features
          are supported:
        -s
    size-S secsize) after suffix
      interpretation.
    If no -s size is
        specified then the filesystem size defaults to that of the partition,
        or, if -F is specified, the existing file.
If size is negative the specified size is subtracted from the default size (reserving space at the end of the partition).
-V
    verbose-N is specified
      newfs_ext2fs stops before outputting the progress
      bar.-v
    volname-Z-F.The following option overrides the standard sizes for the disk
    geometry. The default value is taken from the disk label. Changing this
    default is useful only when using newfs_ext2fs to
    build a file system whose raw image will eventually be used on a different
    type of disk than the one on which it is initially created (for example on a
    write-once disk). Note that changing this value from its default will make
    it impossible for
    fsck_ext2fs(8) to find
    the alternative superblocks if the standard superblock is lost.
-S
    sector-sizeThe file system is created with ‘random’ inode generation numbers to improve NFS security.
The owner and group IDs of the root node and reserved blocks of the new file system are set to the effective UID and GID of the user initializing the file system.
For the newfs_ext2fs command to succeed,
    the disk label should first be updated such that the fstype field for the
    partition is set to
    ‘Linux Ext2’, unless
    -F or -I is used.
The partition size is found using fstat(2), not by inspecting the disk label. The block size and fragment size will be written back to the disk label only if the last character of special references the same partition as the minor device number.
Remy Card, Theodore Ts'o, and Stephen Tweedie, Design and Implementation of the Second Extended Filesystem, The Proceedings of the First Dutch International Symposium on Linux, http://e2fsprogs.sourceforge.net/ext2intro.html.
newfs_ext2fs command first appeared in
  NetBSD 5.0.
newfs_ext2fs command was written by
  Izumi Tsutsui ⟨tsutsui@NetBSD.org⟩.
newfs_ext2fs command is still experimental and there
  are few sanity checks.
The newfs_ext2fs command doesn't have
    options to specify each REV1 file system feature independently.
The newfs_ext2fs command doesn't support
    the bad block list accounted by the bad blocks inode.
Many newer ext2 file system features (especially journaling) are not supported yet.
Some features in file systems created by the
    newfs_ext2fs command might not be recognized
    properly by the
    fsck_ext2fs(8)
  utility.
There is no native tool in the NetBSD distribution for resizing ext2 file systems yet.
| April 13, 2019 | NetBSD 10.0 |