MKFS.BTRFS(8)						      System Manager's Manual						     MKFS.BTRFS(8)

NAME

       mkfs.btrfs - create a btrfs filesystem

SYNOPSIS

       mkfs.btrfs  [ -A alloc-start ] [ -b byte-count ] [ -d data-profile ] [ -f ] [ -n nodesize ] [ -l leafsize ] [ -L label ] [ -m metadata pro-
       file ] [ -M mixed data+metadata ] [ -s sectorsize ] [ -r rootdir ] [ -K ] [ -O feature1,feature2,... ] [ -h ] [ -V ]
	device [ device ... ]

DESCRIPTION

       mkfs.btrfs is used to create a btrfs filesystem (usually in a disk partition, or an array of disk partitions).  device is the special  file
       corresponding  to  the  device  (e.g  /dev/sdXX	).   If  multiple   devices  are specified, btrfs is created spanning across the specified
       devices.

OPTIONS

       -A, --alloc-start offset
	      Specify the offset from the start of the device to start the btrfs filesystem. The default value	is  zero,  or  the  start  of  the
	      device.

       -b, --byte-count size
	      Specify the size of the resultant filesystem. If this option is not used, mkfs.btrfs uses all the available storage for the filesys-
	      tem.

       -d, --data type
	      Specify how the data must be spanned across the devices specified. Valid values are raid0, raid1, raid5, raid6, raid10 or single.

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

       -n, --nodesize size
	      -l,  --leafsize  size Specify the nodesize, the tree block size in which btrfs stores data. The default value is the page size. Must
	      be a multiple of the sectorsize, but not larger than 65536. Leafsize always equals nodesize and the options are aliases.

       -L, --label name
	      Specify a label for the filesystem.

       -m, --metadata profile
	      Specify how metadata must be spanned across the devices specified. Valid values are raid0, raid1, raid5, raid6,  raid10,	single	or
	      dup.   Single  device will have dup set by default except in the case of SSDs which will default to single. This is because SSDs can
	      remap blocks internally so duplicate blocks could end up in the same erase block which negates the benefits of doing metadata dupli-
	      cation.

       -M, --mixed
	      Mix  data  and  metadata	chunks together for more efficient space utilization.  This feature incurs a performance penalty in larger
	      filesystems.  It is recommended for use with filesystems of 1 GiB or smaller.

       -s, --sectorsize size
	      Specify the sectorsize, the minimum data block allocation unit. The default value is the page size. If the sectorsize  differs  from
	      the  page  size,	the  created filesystem may not be mountable by current kernel. Therefore it is not recommended to use this option
	      unless you are going to mount it on a system with the appropriate page size.

       -r, --rootdir rootdir
	      Specify a directory to copy into the newly created fs.

       -K, --nodiscard
	      Do not perform whole device TRIM operation by default.

       -O, --features feature1,feature2,...
	      A list of filesystem features turned on at mkfs time. Not all features are supported by old kernels.

	      To see all run

	      mkfs.btrfs -O list-all

       -V, --version
	      Print the mkfs.btrfs version and exit.

UNIT

       As default the unit is the byte, however it is possible to append a suffix to the arguments like k for KBytes, m for MBytes...

AVAILABILITY

       mkfs.btrfs is part of btrfs-progs. Btrfs is currently under heavy development, and not suitable for any uses other  than  benchmarking  and
       review.	Please refer to the btrfs wiki http://btrfs.wiki.kernel.org for further details.

SEE ALSO

       btrfsck(8)

																     MKFS.BTRFS(8)