USB drive recognized in logs, but no device file for it

Question

I'm trying to mount a flash drive (16 GB Cruzer) on my Arch Linux desktop. It works fine on my Arch Linux laptop, so it's not a problem with the drive.

The drive is in /var/log/messages.log.3:

Dec 16 20:20:45 localhost kernel: [5876090.739078] usb 2-2: new high speed USB device number 2 using ehci_hcd

It's in lsusb:

Bus 002 Device 002: ID 0781:5530 SanDisk Corp. Cruzer

But it's not showing up when I run fdisk -l as root (ignore the errors; they're from all the GUID Partition Tables I have on my other drives):

WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sda: 64.0 GB, 64023257088 bytes
255 heads, 63 sectors/track, 7783 cylinders, total 125045424 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1   125045423    62522711+  ee  GPT

WARNING: GPT (GUID Partition Table) detected on '/dev/sdb'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdb: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1  3907029167  1953514583+  ee  GPT

WARNING: GPT (GUID Partition Table) detected on '/dev/sdd'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdd: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdd1               1  3907029167  1953514583+  ee  GPT

WARNING: GPT (GUID Partition Table) detected on '/dev/sde'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sde: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sde1               1  3907029167  1953514583+  ee  GPT

WARNING: GPT (GUID Partition Table) detected on '/dev/sdf'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdf: 2000.4 GB, 2000397852160 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907027055 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdf1               1  3907027054  1953513527   ee  GPT

WARNING: GPT (GUID Partition Table) detected on '/dev/sdc'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdc: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdc1               1  3907029167  1953514583+  ee  GPT

WARNING: GPT (GUID Partition Table) detected on '/dev/sdg'! The util fdisk doesn't support GPT. Use GNU Parted.


Disk /dev/sdg: 2000.4 GB, 2000397852160 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907027055 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

   Device Boot      Start         End      Blocks   Id  System
/dev/sdg1               1  3907027054  1953513527   ee  GPT

Disk /dev/mapper/root: 26.8 GB, 26841448448 bytes
255 heads, 63 sectors/track, 3263 cylinders, total 52424704 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/root doesn't contain a valid partition table

Disk /dev/md127: 8001.6 GB, 8001580695552 bytes
2 heads, 4 sectors/track, 1953510912 cylinders, total 15628087296 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 524288 bytes / 2097152 bytes
Disk identifier: 0xe8070000

Disk /dev/md127 doesn't contain a valid partition table

Disk /dev/mapper/home: 36.0 GB, 35967540736 bytes
255 heads, 63 sectors/track, 4372 cylinders, total 70249103 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/home doesn't contain a valid partition table

Disk /dev/mapper/data: 8001.6 GB, 8001578598400 bytes
255 heads, 63 sectors/track, 972803 cylinders, total 15628083200 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 524288 bytes / 2097152 bytes
Disk identifier: 0x00000000

Disk /dev/mapper/data doesn't contain a valid partition table

It doesn't show up as a device file in /dev either:

# ls /dev/sd*
/dev/sda  /dev/sda1  /dev/sda2  /dev/sda3  /dev/sda4  /dev/sda5  /dev/sdb  /dev/sdb1  /dev/sdc  /dev/sdc1  /dev/sdd  /dev/sdd1  /dev/sde  /dev/sde1  /dev/sdf  /dev/sdf1  /dev/sdg  /dev/sdg1

These are all my regular hard drives, as you can see from the fdisk output above.

Solution

This message is for recognised USB device. Normally you should also see messages about mass storage, notable about the drive capacity.

Try modprobe usb-storage to load driver for flash disks.

Comments

[Samir Unni]

It was a kernel module problem. I'd just updated the kernel, so all it took was a reboot.