mkfs_vxfs(1M)															     mkfs_vxfs(1M)

NAME

       mkfs_vxfs: mkfs - construct a VxFS file system

SYNOPSIS

       [generic_options] specific_options] special [size]

DESCRIPTION

       The  command  constructs  a file system by writing on the special device file (for example, unless the flag is provided.  special specifies
       the special device file location (or character device node) of a particular storage device.  The  numeric  size	specifies  the	number	of
       1024-byte sectors in the file system.  If size is not specified, 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 to indicate the value is in kilobytes;
       to indicate megabytes; to indicate gigabytes; or to indicate terabytes.	An appended letter can be separated from the number by a  spac	by
       enclosing the letter and number in a set of quotes (for example, "512 k").

       The  command  builds  a	file system with a root directory and a lost+found directory (see fsck(1M)).  The file system can have disk layout
       Version 4, Version 5, or Version 6.  Version 4 adds support for large files and Access Control Lists.  Version 5 adds support for  32  ter-
       abyte  file  systems.  Version 6 adds support for 256 terabyte file systems and various extended VxFS features such as multi-volume support
       and cross-platform data sharing.  The default is Version 6.

       The number of inodes allocated to a file system depends on the disk layout version.  Inodes are allocated dynamically.  There are a minimum
       number of inodes allocated to the file system by and any other inode allocations are done on an as-needed basis during file system use.

NOTES

       The size argument is ignored when the volume is part of a volume set.  The full size of each volume is used instead.

       The  output  of	the option is not sufficient to recreate a multi-volume file system.  The command fails if the option's output is used for
       this purpose.

OPTIONS

       generic_options
		 Supported by the generic command (see mkfs(1M)).

       Specifies the VxFS file system type.

       Displays the command line that was used to create the file system.
		 The file system must already exist.  This option also enables you to determine the parameters used to construct the file system.

       Echoes the completed command line, but does not perform the action.
		 The command line is generated by incorporating the specified options and arguments  with  other  information  derived	from  This
		 option allows the user to verify the command line.

       Specifies the VxFS-specific
		 options in a comma-separated list.

		 The arguments and are no longer supported.  The following arguments are available:

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

		 Creates a file system in a file.
		      Used for debugging only; size must be specified.

		 bsize
		      is  the block size for files on the file system and represents the smallest amount of disk space allocated to a file.  bsize
		      must be a power of 2 selected from the range 1024 bytes to 8192 bytes.  The default is 1024 bytes for file  systems  smaller
		      than  two  terabytes.   For  file  systems larger than two terabytes, the maximum file system size is dependent on the block
		      size.  A block size of 1 KB allows a maximum file system size of up to 32 terabytes, a block size of 2 KB allows	a  maximum
		      file system size of up to 64 terabytes, a block size of 4 KB allows a maximum file system size of up to 128 terabytes, and a
		      block size of 8 KB allows for a file system up to 256 terabytes.	These maximum sizes are for disk layout  Version  6.   The
		      actual maximum file system sizes are slightly less than the above values.  The exact values can be found in the Veritas File
		      System Administrator's Guide.  If bsize is not specified, the block size defaults to the appropriate value when a file  sys-
		      tem is created.

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

		 Controls the
		      flag  for  the file system.  If is specified, the bit is set and files two gigabytes or larger can be created.  If is speci-
		      fied, the bit is cleared and files created on the file system are limited to  less  than	two  gigabytes.   The  default	is
		      mkfs(1M) and fsadm_vxfs(1M)).

		      VxFS  file systems are created by default with the option enabled.  Be sure that any system administration utilities used on
		      VxFS file systems, such as backup, operate on large files.

		 n    is the number of file system blocks to allocate for an activity logging area.  The minimum value is  the	number	of  blocks
		      that  make  the  log no less than 256 KB.  The maximum value for n is the number of blocks that make the log no greater than
		      262,144 kilobytes (256 MB) on a file system with disk layout Version 6, or 16,384 kilobytes (16 MB) on a	file  system  with
		      disk layout Version 4 or 5.  For a small file system, the default may be smaller to avoid wasting space.

		      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, an NFS-intensive workload performs better with a large log;  a  small  floppy  device
		      requires a small log.

		      The  amount of virtual memory required by (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 16384 KB log can be cleaned.  On small systems, be
		      careful 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 general rule.  See swapinfo(1M).

		 n    is  the  VxFS  disk layout version number.  Valid values are 4, 5, and 6.  Version 6 disk layouts support file systems up to
		      256 terabytes in size, although file systems currently cannot be created with a size of 8 exabytes.   The  default  is  disk
		      layout Version 6.

EXAMPLES

       Create a VxFS file system on Veritas Volume Manager volume at the special device file /dev/vx/rdsk/dg1/vol1 with a size of 1 GB.

       Determine the block size, disk layout version, inode size, log size, and device size of a VxFS file system.

SEE ALSO

       fsadm_vxfs(1M), fsck(1M), fsck_vxfs(1M), mkfs(1M), mount_vxfs(1M), swapinfo(1M), dir(4), fs_vxfs(4).

       Veritas Volume Manager Administrator's Guide

																     mkfs_vxfs(1M)