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mkfs.btrfs(8) [centos man page]

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)

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MKFS.MINIX(8)						       System Administration						     MKFS.MINIX(8)

NAME
mkfs.minix - make a Minix filesystem SYNOPSIS
mkfs.minix [options] device [size-in-blocks] DESCRIPTION
mkfs.minix creates a Linux MINIX filesystem on a device (usually a disk partition). The device is usually of the following form: /dev/hda[1-8] (IDE disk 1) /dev/hdb[1-8] (IDE disk 2) /dev/sda[1-8] (SCSI disk 1) /dev/sdb[1-8] (SCSI disk 2) The device may be a block device or a image file of one, but this is not enforced. Expect not much fun on a character device :-). The size-in-blocks parameter is the desired size of the file system, in blocks. It is present only for backwards compatibility. If omit- ted the size will be determined automatically. Only block counts strictly greater than 10 and strictly less than 65536 are allowed. OPTIONS
-c, --check Check the device for bad blocks before creating the filesystem. If any are found, the count is printed. -n, --namelength length Specify the maximum length of filenames. Currently, the only allowable values are 14 and 30 for file system versions 1 and 2. Ver- sion 3 allows only value 60. The default is 30. -i, --inodes number Specify the number of inodes for the filesystem. -l, --badblocks filename Read the list of bad blocks from filename. The file has one bad-block number per line. The count of bad blocks read is printed. -1 Make a Minix version 1 filesystem. This is the default. -2, -v Make a Minix version 2 filesystem. -3 Make a Minix version 3 filesystem. -V, --version Display version information and exit. The long option cannot be combined with other options. -h, --help Display help text and exit. EXIT CODES
The exit code returned by mkfs.minix is one of the following: 0 No errors 8 Operational error 16 Usage or syntax error SEE ALSO
fsck(8), mkfs(8), reboot(8) AVAILABILITY
The mkfs.minix command is part of the util-linux package and is available from https://www.kernel.org/pub/linux/utils/util-linux/. util-linux June 2015 MKFS.MINIX(8)

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