Post the

dmesg

log from circa second 7 -

Begins with

• '[    7.320674] scsi 0:0:0:0: Direct-Access ...'

up to and including

• '[    7.366148] sd 0:0:0:0: [sda] Attached SCSI removable disk'

The precise message of interest is '[    7.359355]  sda: sda1 ...'

[   10.340000] scsi 0:0:0:0: Direct-Access     Corsair  Flash Voyager    1100 PQ: 0 ANSI: 0 CCS
[   10.350000] sd 0:0:0:0: [sda] 3964928 512-byte logical blocks: (2.03 GB/1.89 GiB)
[   10.370000] sd 0:0:0:0: [sda] Write Protect is off
[   10.370000] sd 0:0:0:0: [sda] Mode Sense: 43 00 00 00
[   10.370000] sd 0:0:0:0: [sda] No Caching mode page found
[   10.380000] sd 0:0:0:0: [sda] Assuming drive cache: write through
[   10.390000]  sda: sda1
[   10.400000] sd 0:0:0:0: [sda] Attached SCSI removable disk
[   10.890000] procd: - ubus -
[   11.910000] procd: - init -

Which device, which OpenWrt version?

TP-Link TL-WR1043N/ND v2
OpenWrt Chaos Calmer 15.05 / LuCI (git-15.248.30277-3836b45)

@StacK - Thank-you for the informations.

Honest to say I see nothing incorrect with the outputs:

• (success recognising the device)
  [   10.390000]  sda: sda1
  [   10.400000] sd 0:0:0:0: [sda] Attached SCSI removable disk

• (the mount point exists)
  mkdir /mnt/vfat

• (/etc/fstab is not referenced)
  mount -t vfat /dev/sda1 /mnt/vfat

About this -

root@OpenWrt:~# mount -t vfat /dev/sda1
mount: can't read '/etc/fstab': No such file or directory

The mount program does not read the /etc/fstab file if device (or LABEL/UUID) and dir are specified.

Thus, here I can only think the LABEL of the device is not accepted by mount (which is unthinkable).

EDIT: testing on a device without the required (for vfat) codepages (kmod-nls-cp437 and kmod-nls-iso8859-1) results in the 'Invalid argument' message.

For some filesystems, like for VFAT, you need to additionally install language packages (codepages / charsets) to handle the filenames. If your mount fails, look in dmesg - a message like

FAT: codepage cp437 not found

means that you need NLS codepage 437, and a message like

FAT: IO charset iso8859-1 not found

means that you need NLS ISO 8859-1.

N.B. dmesg does not contain these messages @ r47142 (DD)

@Max Hopper,

Thank you very much for your help.
Unfortunately it is not clear for me whether there is any problem and where is it.

Post the output of

opkg list-installed kmod-nls*

Or -

opkg update; opkg install kmod-nls-cp437 kmod-nls-iso8859-1

root@OpenWrt:~# opkg list-installed kmod-nls*
kmod-nls-base - 3.18.20-1

And after installation:

kmod-nls-base - 3.18.20-1
kmod-nls-cp437 - 3.18.20-1
kmod-nls-iso8859-1 - 3.18.20-1

And again:

root@OpenWrt:~# mount -t vfat /dev/sda1
mount: can't read '/etc/fstab': No such file or directory

Still not visible in dev.

Edit: I've missed to reboot. Now sda1 is visible in dev.
Thank you both, guys.
Good night

(Last edited by StacK on 5 Feb 2016, 00:46)

same problem, I followed all the steps described above and is not visible in the UUID usb section, dmesg output :

[  639.970000] dwc2 101c0000.otg: Overcurrent change detected
[  639.980000] dwc2 101c0000.otg: Overcurrent change detected
[  640.210000] dwc2 101c0000.otg: Overcurrent change detected
[  640.220000] dwc2 101c0000.otg: Overcurrent change detected
...
...

help please

(Last edited by juancalopez on 20 Sep 2016, 17:38)

Hit the same issue and spent a good hour trying to figure out what was wrong, all the mods installed and usb was added as /dev/sda1, but could not mount it.

In my case the usb was brand new and had no fs, ran mkfs.ext4 to format it now it works.