3 mkfs.exfat \- create an exFAT filesystem
35 creates an exFAT filesystem by writing on a special
36 file using the values found in the arguments of the command line.
37 It is invoked automatically by
43 As an example, to make a filesystem on the first partition on the first
46 .B mkfs.exfat /dev/sda1
50 .BR \-b ", " \-\-boundary\-align =\fIalignment\fR
51 Specifies the alignment for the FAT and the start of the cluster heap.
52 The \fIalignment\fR argument is specified in bytes or may be specified with
53 \fBm\fR/\fBM\fR suffix for mebibytes or \fBk\fR/\fBK\fR suffix for kibibytes
54 and should be a power of two.
55 Some media like SD cards need this for optimal performance and endurance,
56 in which case \fIalignment\fR should be set to half of the card's native
58 If the card's native boundary unit size is not known, refer to the following
59 table of boundary unit sizes recommended by the SD Card Association.
60 .\" source: SD Specifications Part 2: File System Specification Version 3.00
64 Card Capacity Range Cluster Size Boundary Unit
66 \[<=]8 MiB 8 KiB 8 KiB
67 >8 MiB \[<=]64 MiB 16 KiB 16 KiB
68 >64 MiB \[<=]256 MiB 16 KiB 32 KiB
69 >256 MiB \[<=]1 GiB 16 KiB 64 KiB
70 >1 GiB \[<=]2 GiB 32 KiB 64 KiB
71 >2 GiB \[<=]32 GiB 32 KiB 4 MiB
72 >32 GiB \[<=]128 GiB 128 KiB 16 MiB
73 >128 GiB \[<=]512 GiB 256 KiB 32 MiB
74 >512 GiB \[<=]2 TiB 512 KiB 64 MiB
76 The default is always 1 MiB.
78 .BR \-s ", " \-\-sector\-size =\fIsize\fR
79 Specifies the sector size of the exFAT file system.
80 The \fIsize\fR argument is specified in bytes or may be specified with
81 \fBk\fR/\fBK\fR suffix for kibibytes and must either 512, 1024, 2048 or 4096
83 The default value is the sector size reported by the device, or 512 bytes if the
84 device sector size cannot be determined.
86 .BR \-c ", " \-\-cluster\-size =\fIsize\fR
87 Specifies the cluster size of the exFAT file system.
88 The \fIsize\fR argument is specified in bytes or may be specified with
89 \fBm\fR/\fBM\fR suffix for mebibytes or \fBk\fR/\fBK\fR suffix for kibibytes
90 and must be a power of two.
91 The default value is described in the following table:
95 Card Capacity Range Cluster Size
98 >256 MiB \[<=]32 GiB 32 KiB
102 .BR \-f ", " \-\-full\-format
103 Performs a full format.
104 This zeros the entire disk device while creating the exFAT filesystem.
106 .BR \-h ", " \-\-help
107 Prints the help and exit.
109 .BR \-L ", " \-\-volume\-label =\fIlabel\fR
110 Specifies the volume label to be associated with the exFAT filesystem.
112 .BR \-U ", " \-\-volume\-guid =\fIguid\fR
113 Specifies the volume GUID to be associated with the exFAT filesystem.
116 Attempts to relocate the exFAT allocation bitmap so that it ends at the
117 alignment boundary immediately following the FAT rather than beginning at that
119 This strictly violates the SD card specification but may improve performance
120 and endurance on SD cards and other flash media not designed for use with exFAT
121 by allowing file-system metadata updates to touch fewer flash allocation units.
122 Furthermore, many SD cards and other flash devices specially optimize the
123 allocation unit where the FAT resides so as to support tiny writes with reduced
124 write amplification but expect only larger writes in subsequent allocation
125 units \[em] where the exFAT bitmap would be placed by default.
126 Specifying \fB\-\-pack\-bitmap\fR attempts to avoid the potential problems
127 associated with issuing many small writes to the bitmap by making it share an
128 allocation unit with the FAT.
129 If there is insufficient space for the bitmap there, then this option will have
130 no effect, and the bitmap will be aligned at the boundary as by default.
132 .BR \-q ", " \-\-quiet
133 Prints only error messages while creating the exFAT filesystem.
135 .BR \-v ", " \-\-verbose
136 Prints verbose debugging information while creating the exFAT filesystem.
138 .BR \-V ", " \-\-version
139 Prints the version number and exits.