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 profile ] [ -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 filesystem.

       -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
              duplication.

       -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-tools. 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)