Mounting exFat device

[David Christensen]

On 3/8/21 8:27 AM, Steven Friedrich wrote:



Here is one of my FreeBSD systems:

2021-03-08 14:53:03 toor at f2 ~
# freebsd-version
12.2-RELEASE-p4

2021-03-08 14:53:08 toor at f2 ~
# uname -a
FreeBSD f2.tracy.holgerdanske.com 12.2-RELEASE-p4 FreeBSD 
12.2-RELEASE-p4 GENERIC  amd64


Here is a SanDisk Cruzer Glide with the original factory format (FAT32 
or whatever; there are too many variants):

2021-03-08 14:53:09 toor at f2 ~
# camcontrol devlist | grep -i sandisk
<SanDisk Cruzer Glide 1.00>        at scbus7 target 0 lun 0 (pass2,da0)

2021-03-08 14:53:26 toor at f2 ~
# gpart show da0
=>        1  122585087  da0  MBR  (58G)
           1         31       - free -  (16K)
          32  122585056    1  fat32lba  (58G)

2021-03-08 14:53:41 toor at f2 ~
# gpart list da0
Geom name: da0
modified: false
state: OK
fwheads: 255
fwsectors: 63
last: 122585087
first: 1
entries: 4
scheme: MBR
Providers:
1. Name: da0s1
    Mediasize: 62763548672 (58G)
    Sectorsize: 512
    Stripesize: 0
    Stripeoffset: 16384
    Mode: r0w0e0
    efimedia: HD(1,MBR,00000000,0x20,0x74e7fe0)
    rawtype: 12
    length: 62763548672
    offset: 16384
    type: fat32lba
    index: 1
    end: 122585087
    start: 32
Consumers:
1. Name: da0
    Mediasize: 62763565056 (58G)
    Sectorsize: 512
    Mode: r0w0e0

2021-03-08 14:55:32 toor at f2 ~
# mkdir /mnt/da0s1

2021-03-08 14:56:56 toor at f2 ~
# mount /dev/da0s1 /mnt/da0s1
mount: /dev/da0s1: No such file or directory

2021-03-08 14:57:04 toor at f2 ~
# l /dev/da*
/dev/da0	/dev/da0s1


I believe the error message is misleading -- device node /dev/da0s1 
exists, but mount(8) is failing because it cannot determine the type of 
the filesystem on da0s1 (?).


STFW the solution is to provide the correct 't type' option to mount(8):

2021-03-08 15:05:15 toor at f2 ~
# mount -v -t msdosfs /dev/da0s1 /mnt/da0s1
/dev/da0s1 on /mnt/da0s1 (msdosfs, local, writes: sync 1 async 0, reads: 
sync 1872 async 0, fsid a400000032000000)

2021-03-08 15:13:22 toor at f2 ~
# mount | grep da0
/dev/da0s1 on /mnt/da0s1 (msdosfs, local)

2021-03-08 15:13:37 toor at f2 ~
# l /mnt/da0s1
./					SanDiskSecureAccess/
../					SanDiskSecureAccessV3.1_win.exe*
README.TXT*				firmware/

2021-03-08 15:19:49 toor at f2 ~
# umount /mnt/da0s1


David