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 mkfs_vxfs(1M)						       mkfs_vxfs(1M)




 NAME
      mkfs - construct a VxFS file system

 SYNOPSIS
      /usr/sbin/mkfs [-F vxfs] [-V] -m special

      /usr/sbin/mkfs [-F vxfs] [-V]
	   [-o [N] [X] [ninode=n] [nau=n] [bsize=n] [logsize=n] [ausize=n]
	   [aufirst=n] [aupad=n] [version=n] [inosize=n]
	   [largefiles|nolargefiles] ] special size

 DESCRIPTION
      mkfs creates a VxFS file system by writing on the special device file,
      unless either the -o N or -m option is specified.	 special must be the
      first argument after the options are given.  The file system is
      created based on the options and size specified on the command line.
      The numeric size specifies the number of sectors in the file system.
      By default, size is specified in units of DEV_BSIZE sectors
      (currently, 1024 bytes).	If size is not specified, mkfs determines
      the size of the special device.

      size can also be specified with a suffix to indicate a unit of measure
      other than sectors.  Append k or K to indicate the value is in
      kilobytes, m or M to indicate megabytes, or g or G to indicate
      gigabytes.  An appended letter can be separated from the number by a
      space.  In that case, enclose the letter and number in a set of
      quotes, for example:

	   "512 k"

      mkfs builds a file system with a root directory and a lost+found
      directory (see fsck_vxfs(1M)).  The file system can have disk layout
      Version 2, disk layout Version 3, or disk layout Version 4.  Version 2
      supports dynamic inode allocation.  Version 3 adds support for large
      files and large UIDs.  Version 4 adds support for Access Control
      Lists.  On HP-UX 11.1x systems, the default is Version 4.	 On HP-UX
      11.0 systems, the default is Version 3.  You can choose the disk
      layout version with the version=n option (see below).

      Inode allocation is done dynamically.  There are a minimum number of
      inodes allocated to the file system by mkfs, and any other inode
      allocations are done on an as-needed basis during file system use.

    Options
      mkfs recognizes the following options:

	   -F vxfs	  Specify the VxFS file system type.

	   -m		  Display the command line which was used to create
			  the file system.  The file system must already
			  exist.



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	   -V		  Echo the completed command line, but do not
			  execute the command.	The command line is
			  generated by incorporating the user-specified
			  options and other information derived from
			  /etc/fstab.  This option allows the user to verify
			  the command line.

	   -o specific_options
			  Specify options specific to the VxFS file system
			  type.	 specific_options is a comma separated list
			  of suboptions and/or keyword/attribute pairs.

			  The following specific_options are valid on a VxFS
			  file system:

			  N    Do not write the file system to the special
			       file.  This option gives all the information
			       needed to create a file system but does not
			       create it.

			  X    Create a file system in a file.	Used for
			       debugging only.

			  aufirst=n
			       n is the starting block number, in blocks of
			       size bsize, of the first allocation unit.
			       This option allows the allocation units to be
			       aligned to a particular boundary, such as a
			       cylinder boundary.  This option is not
			       applicable to Version 3 and 4 disk layouts,
			       which always set the starting block number to
			       zero.

			  aupad=n
			       n is the size, in blocks of size bsize, of
			       the padding to leave between the end of the
			       inode list and the first data block in each
			       allocation unit. This option allows the data
			       blocks of an allocation unit to be aligned to
			       a particular boundary, such as a cylinder
			       boundary.  This option is ignored for Version
			       3 and 4 disk layouts.

			  ausize=n
			       n is the size, in blocks of size bsize, of an
			       allocation unit.	 This option is not
			       applicable to the Version 3 and 4 disk
			       layouts, which fix the allocation unit size
			       at 32768.  For disk layout Version 2, this is
			       an alternate way of specifying the number of
			       allocation units.  This option cannot be used



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			       with the nau option.  With ausize, the last
			       allocation unit on the file system can be
			       shorter than the others. If the last
			       allocation unit on the file system is not
			       long enough to contain an entire allocation
			       unit header, the size of the resulting file
			       system is shortened to the end of the last
			       complete allocation unit.  This parameter may
			       not exceed 262144 blocks.

			       The algorithm used to choose the default
			       value is rather complicated, but is intended
			       to balance the number of allocation units (4
			       to 16 is a good range), the size of the
			       allocation units (at least 32768 blocks), and
			       other factors.

			  bsize=n
			       n is the block size for files on the file
			       system and represents the smallest amount of
			       disk space allocated to a file.	n must be a
			       power of 2 selected from the range 1024 to
			       8192.  The default is 1024 for file systems
			       less than 8 gigabytes, 2048 for file systems
			       less than 16 gigabytes, 4096 for file systems
			       less than 32 gigabytes, and 8192 for larger
			       file systems.

			  inosize=n
			       n is the on-disk inode structure size for
			       files on the file system.  The valid values
			       are 256 and 512 bytes.  The default is 256.
			       There is usually no reason to increase the
			       inode size, and not using the default value
			       can adversely affect file system performance.

			  largefiles|nolargefiles
			       Valid only for the Version 3 and 4 disk
			       layouts.	 Controls the largefiles flag for
			       the file system.	 If largefiles is specified,
			       the bit is set and files two gigabytes or
			       larger can be created.  If nolargefiles is
			       specified, the bit is cleared and files
			       created on the file system are limited to
			       less than two gigabytes.	 The default is
			       nolargefiles.  See fsadm_vxfs(1M).

			       NOTE: Large files are supported on HP-UX
			       10.20 systems and above.	 Be careful when
			       implementing large file system capability.
			       System administration utilities such as



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			       backup may not operate correctly if they are
			       not large-file aware.

			  logsize=n
			       n is the number of file system blocks to
			       allocate for an activity logging area.  The
			       minimum value for Version 2 and 3 disk
			       layouts is 32 blocks.  The minimum value for
			       Version 4 disk layouts is the number of
			       blocks that make the log no less than 256K.
			       The maximum value for n is the number of
			       blocks that make the log no greater than
			       16384K.	This means that for a bsize of 1024,
			       2048, 4096, or 8192 bytes the maximum value
			       of logsize is 16384, 8192, 4096, or 2048
			       blocks, respectively.  To avoid wasting
			       space, the default logsize is 1024 blocks for
			       a file system 8 megabytes or larger, 128
			       blocks for a file system 2 megabytes or
			       larger but less than 8 megabytes, and 32
			       blocks for a file system less than 2
			       megabytes.

			       A large log provides better performance on
			       metadata-intensive workloads.  A small log
			       uses less space on the disk and leaves more
			       room for file data.  for example, and NFS-
			       intensive workload performs better with a
			       large log; a small floppy device requires a
			       small log.

			       NOTE: The amount of virtual memory required
			       by fsck (see fsck_vxfs(1M)) to check a VxFS
			       file system is proportional to the size of
			       the log.	 The maximum amount of virtual
			       memory used is twice the size of the log.
			       Therefore, the sum of physical memory and
			       swap space must be at least 32 MB to ensure
			       that a file system with a 16384K log can be
			       cleaned.	 On small systems, take care not to
			       create a file system with a log larger than
			       half the available swap space.  A maximum log
			       size of one third the total of memory and
			       swap space is a good rule of thumb (see
			       swapinfo(1M)).

			  nau=n
			       n is the number of allocation units on the
			       file system.  This option is not applicable
			       to the Version 3 and 4 disk layouts.  For
			       disk layout Version 2, if nau is specified,



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			       then ausize is determined by evenly dividing
			       the sectors among the allocation units.	By
			       default, the number of allocation units is
			       based on the value of ausize.

			  ninode=n
			       n is the maximum number of inodes in the file
			       system.	The actual maximum number of inodes
			       is n rounded up to an appropriate boundary.
			       The digit 0 and the string unlimited both
			       mean that the number of inodes is unlimited.
			       The default is unlimited.

			  version=n
			       n is the VxFS disk layout version number.
			       Valid values are 2, 3, and 4.

 EXAMPLES
      To use mkfs to create a VxFS file system on /dev/rdsk/c0t6d0:

	   mkfs -F vxfs /dev/rdsk/c0t6d0 1024

      To use mkfs to determine the command that was used to create the VxFS
      file system on /dev/rdsk/c0t6d0:

	   mkfs -F vxfs -m /dev/rdsk/c0t6d0

      To create a VxFS file system on /dev/vgqa/lvol1, with a Version 4 disk
      layout and largefiles capability:

	   mkfs -F vxfs -o version=4,largefiles /dev/vgqa/lvol1

 WARNINGS
      If you want to reuse a special device that was previously used by LVM,
      you must first wipe out all the LVM information remaining on the disk.
      Use pvremove(1M) to remove the LVM information before executing
      mkfs_vxfs(1M).  (You can also remove the LVM information by
      initializing the device with mediainit(1), but that is slower.)

      The -o largefiles option should be used with care, since older
      applications will not react correctly when confronted with large
      files.

 RETURN VALUE
      Upon successful completion, the mkfs command returns a value of 0.
      The return value is 1 if a syntax error occurs.  Other errors return a
      value of 32.

 SEE ALSO
      bdf(1M), chmod(1), chown(2), df_vxfs(1M), fs_vxfs(4), fsadm_vxfs(1M),
      fsck_vxfs(1M), group(4), mkfs(1M), mount_vxfs(1M), newfs_vxfs(1M),



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      passwd(4), pvremove(1M).

 STANDARDS CONFORMANCE
      mkfs : SVID3


















































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