Not any file system on any USB stick will found on /dev/sd(X), it always will be on /dev/sd(X)1 or higher.

Use any stick with FAT32, you have to mount it with /dev/sd(X)1.

rolfie

I dont have much knowledge on this but i can format a usb like so and it is usable and i am able to mount it read write.

# mkfs.exfat /dev/sdb

same with fat32.

I think it is just using the whole block device as filesystem only.

Essentially it looks like you sit with software that "expects" exfat to be a built-in filesystem (as in beowulf-backports and later), and a kernel where it's not (as in beowulf and before).

The story seems to be that:

a) exfat is a built-in filesystem for 5.10 kernels but it wasn't built-in for the 4.9 kernels.

b) Before it became built-in, the mount command was supported by the program /sbin/mount.exfat provided by the exfat-fuse package. That program was abandoned when the filesystem became built-in.

Damn, you're right. I checked /boot/config and my kernel has:

CONFIG_EXFAT_FS is not set

Case closed.

Thanks for all the help.

Not any file system on any USB stick will found on /dev/sd(X), it always will be on /dev/sd(X)1 or higher.

Use any stick with FAT32, you have to mount it with /dev/sd(X)1.

rolfie

I just created a filesystem on /dev/sdb with vfat and had no problems mounting it. vfat is the same as fat32 is it not?

Use any stick with FAT32, you have to mount it with /dev/sd(X)1.

rolfie

The story seems to be that:

a) exfat is a built-in filesystem for 5.10 kernels but it wasn't built-in for the 4.9 kernels.

b) Before it became built-in, the mount command was supported by the program /sbin/mount.exfat provided by the exfat-fuse package. That program was abandoned when the filesystem became built-in.

maybe try this command ?

# mount -t exfat /dev/sdc /mnt/

if that doesnt work trying installing exfatprogs and use command like so.

# mount.exfat-fuse /dev/sdc /mnt

Using my newly partitioned USB stick that has 1 partition:

# mount -t exfat  /dev/sdb1 /mnt
mount: /mnt: unknown filesystem type 'exfat'.
# mount.exfat-fuse /dev/sdb1 /mnt
FUSE exfat 1.3.0

Thank you - at least I can now mount exfat.

The question then becomes, why does the mount command fail but mount.exfat-fuse work?

devian wrote:

# mount  /dev/sdc /mnt/
mount: /mnt: unknown filesystem type 'exfat'.

This is obvious. You can't have an exfat file system at /dev/sdc, at the most you'll find a partition table there.

Try to use:

# mount  /dev/sdc1 /mnt/

rolfie

There is no partition table on this drive.

I did a test with another USB stick:

[fdisk]
Disk /dev/sdb: 1.86 GiB, 1993342976 bytes, 3893248 sectors
Disk model: Flash Disk      
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x00000000

Device     Boot Start     End Sectors  Size Id Type
/dev/sdb1        2048 3893247 3891200  1.9G 83 Linux

Filesystem/RAID signature on partition 1 will be wiped.

Command (m for help): wq
The partition table has been altered.
Calling ioctl() to re-read partition table.
Syncing disks.

# mkfs.exfat /dev/sdb1
mkexfatfs 1.3.0
Creating... done.
Flushing... done.
File system created successfully.

# mount /dev/sdb1 /mnt
mount: /mnt: unknown filesystem type 'exfat'.

# mount  /dev/sdc /mnt/
mount: /mnt: unknown filesystem type 'exfat'.

This is obvious. You can't have an exfat file system at /dev/sdc, at the most you'll find a partition table there.

Try to use:

# mount  /dev/sdc1 /mnt/

rolfie

# mount -t exfat /dev/sdc /mnt/

if that doesnt work trying installing exfatprogs and use command like so.

# mount.exfat-fuse /dev/sdc /mnt

What are my options to debug this? Thanks.

# lsmod | grep fuse
fuse                  147456  0
# mount  /dev/sdc /mnt/
mount: /mnt: unknown filesystem type 'exfat'.