3 mkfs.exfat \- create an exFAT filesystem
32 creates an exFAT filesystem by writing on a special
33 file using the values found in the arguments of the command line.
34 It is invoked automatically by
40 As an example, to make a filesystem on the first partition on the first
43 .B mkfs.exfat /dev/sda1
47 .BR \-b ", " \-\-boundary\-align =\fIalignment\fR
48 Specifies the alignment for the FAT and the start of the cluster heap.
49 The \fIalignment\fR argument is specified in bytes or may be specified with
50 \fBm\fR/\fBM\fR suffix for mebibytes or \fBk\fR/\fBK\fR suffix for kibibytes
51 and should be a power of two.
52 Some media like SD cards need this for optimal performance and endurance,
53 in which case \fIalignment\fR should be set to half of the card's native
55 If the card's native boundary unit size is not known, refer to the following
56 table of boundary unit sizes recommended by the SD Card Association.
57 .\" source: SD Specifications Part 2: File System Specification Version 3.00
61 Card Capacity Range Cluster Size Boundary Unit
63 \[<=]8 MiB 8 KiB 8 KiB
64 >8 MiB \[<=]64 MiB 16 KiB 16 KiB
65 >64 MiB \[<=]256 MiB 16 KiB 32 KiB
66 >256 MiB \[<=]1 GiB 16 KiB 64 KiB
67 >1 GiB \[<=]2 GiB 32 KiB 64 KiB
68 >2 GiB \[<=]32 GiB 32 KiB 4 MiB
69 >32 GiB \[<=]128 GiB 128 KiB 16 MiB
70 >128 GiB \[<=]512 GiB 256 KiB 32 MiB
71 >512 GiB \[<=]2 TiB 512 KiB 64 MiB
73 The default is always 1 MiB.
75 .BR \-c ", " \-\-cluster\-size =\fIsize\fR
76 Specifies the cluster size of the exFAT file system.
77 The \fIsize\fR argument is specified in bytes or may be specified with
78 \fBm\fR/\fBM\fR suffix for mebibytes or \fBk\fR/\fBK\fR suffix for kibibytes
79 and must be a power of two.
80 The default value is described in the following table:
84 Card Capacity Range Cluster Size
87 >256 MiB \[<=]32 GiB 32 KiB
91 .BR \-f ", " \-\-full\-format
92 Performs a full format.
93 This zeros the entire disk device while creating the exFAT filesystem.
96 Prints the help and exit.
98 .BR \-L ", " \-\-volume\-label =\fIlabel\fR
99 Specifies the volume label to be associated with the exFAT filesystem.
101 .BR \-U ", " \-\-volume\-guid =\fIguid\fR
102 Specifies the volume GUID to be associated with the exFAT filesystem.
105 Attempts to relocate the exFAT allocation bitmap so that it ends at the
106 alignment boundary immediately following the FAT rather than beginning at that
108 This strictly violates the SD card specification but may improve performance
109 and endurance on SD cards and other flash media not designed for use with exFAT
110 by allowing file-system metadata updates to touch fewer flash allocation units.
111 Furthermore, many SD cards and other flash devices specially optimize the
112 allocation unit where the FAT resides so as to support tiny writes with reduced
113 write amplification but expect only larger writes in subsequent allocation
114 units \[em] where the exFAT bitmap would be placed by default.
115 Specifying \fB\-\-pack\-bitmap\fR attempts to avoid the potential problems
116 associated with issuing many small writes to the bitmap by making it share an
117 allocation unit with the FAT.
118 If there is insufficient space for the bitmap there, then this option will have
119 no effect, and the bitmap will be aligned at the boundary as by default.
121 .BR \-q ", " \-\-quiet
122 Prints only error messages while creating the exFAT filesystem.
124 .BR \-v ", " \-\-verbose
125 Prints verbose debugging information while creating the exFAT filesystem.
127 .BR \-V ", " \-\-version
128 Prints the version number and exits.