mkfs.exfat

mkfs.exfat(8) System Manager's Manual mkfs.exfat(8)

NAME

   mkfs.exfat - create an exFAT filesystem

SYNOPSIS

   mkfs.exfat [ -b boundary_alignment ] [ -s sector_size ] [ -c cluster_size ] [ -f ] [ -h ] [ -L volume_label ] [ -U volume_guid ] [ --pack-bitmap ] [ -v ] device
   mkfs.exfat -V

DESCRIPTION

   mkfs.exfat  creates  an  exFAT  filesystem by writing on a special file using the values found in the arguments of the command line.  It is invoked automatically by mkfs(8) when it is
   given the -t exfat option.

   As an example, to make a filesystem on the first partition on the first SCSI disk, use:

          mkfs.exfat /dev/sda1

OPTIONS

   -b, --boundary-align=alignment
          Specifies the alignment for the FAT and the start of the cluster heap.  The alignment argument is specified in bytes or may be specified with m/M suffix for  mebibytes  or  k/K
          suffix  for  kibibytes and should be a power of two.  Some media like SD cards need this for optimal performance and endurance, in which case alignment should be set to half of
          the card's native boundary unit size.  If the card's native boundary unit size is not known, refer to the following table of boundary unit sizes recommended by the SD Card  As‐
          sociation.
                                                                       Card Capacity Range      Cluster Size   Boundary Unit
                                                                       ──────────────────────────────────────────────────────
                                                                                   ≤8 MiB           8 KiB          8 KiB
                                                                         >8 MiB   ≤64 MiB          16 KiB         16 KiB
                                                                        >64 MiB  ≤256 MiB          16 KiB         32 KiB
                                                                       >256 MiB    ≤1 GiB          16 KiB         64 KiB
                                                                         >1 GiB    ≤2 GiB          32 KiB         64 KiB
                                                                         >2 GiB   ≤32 GiB          32 KiB          4 MiB
                                                                        >32 GiB  ≤128 GiB         128 KiB         16 MiB
                                                                       >128 GiB  ≤512 GiB         256 KiB         32 MiB
                                                                       >512 GiB    ≤2 TiB         512 KiB         64 MiB
          The default is always 1 MiB.

   -s, --sector-size=size
          Specifies  the  sector size of the exFAT file system.  The size argument is specified in bytes or may be specified with k/K suffix for kibibytes and must either 512, 1024, 2048
          or 4096 bytes.  The default value is the sector size reported by the device, or 512 bytes if the device sector size cannot be determined.

   -c, --cluster-size=size
          Specifies the cluster size of the exFAT file system.  The size argument is specified in bytes or may be specified with m/M suffix for mebibytes or k/K suffix for kibibytes  and
          must be a power of two.  The default value is described in the following table:
                                                                               Card Capacity Range      Cluster Size
                                                                               ──────────────────────────────────────
                                                                                         ≤256 MiB           4 KiB
                                                                               >256 MiB   ≤32 GiB          32 KiB
                                                                                >32 GiB                   128 KiB

   -f, --full-format
          Performs a full format.  This zeros the entire disk device while creating the exFAT filesystem.

   -h, --help
          Prints the help and exit.

   -L, --volume-label=label
          Specifies the volume label to be associated with the exFAT filesystem.

   -U, --volume-guid=guid
          Specifies  the  volume GUID to be associated with the exFAT filesystem.  It can be given in the standard, hypenized UUID format like aaaabbbb-cccc-dddd-eeee-ffff00001111. Note:
          The volume GUID cannot be used to set the the 8-letter ID reported by blkid or used as the filesystem UUID in /etc/fstab.

   --pack-bitmap
          Attempts to relocate the exFAT allocation bitmap so that it ends at the alignment boundary immediately following the FAT rather than beginning at that boundary.  This  strictly
          violates  the SD card specification but may improve performance and endurance on SD cards and other flash media not designed for use with exFAT by allowing file-system metadata
          updates to touch fewer flash allocation units.  Furthermore, many SD cards and other flash devices specially optimize the allocation unit where the FAT resides so as to support
          tiny writes with reduced write amplification but expect only larger writes in subsequent allocation units — where the exFAT bitmap  would  be  placed  by  default.   Specifying
          --pack-bitmap  attempts to avoid the potential problems associated with issuing many small writes to the bitmap by making it share an allocation unit with the FAT.  If there is
          insufficient space for the bitmap there, then this option will have no effect, and the bitmap will be aligned at the boundary as by default.

   -q, --quiet
          Prints only error messages while creating the exFAT filesystem.

   -v, --verbose
          Prints verbose debugging information while creating the exFAT filesystem.

   -V, --version
          Prints the version number and exits.