# USB not automouted, not shown in fdisk

## oz_tiram

Hi Everyone,

I have a SunDisk Cruzer usb disk which is seemlessly recognized when inserted  one  my Gentoo installed laptop.

On the other laptop with Gentoo, the usb is not shown by 

```
fdisk -l
```

, but it does show in

```
 dmesg | tail
```

.

I suspect that the cause of the problem is that the Lexmark MX510 I am using is messing up with the disk. I use the function scan

to Disk, and I don't know how to remove the drive safely. Which I think causes the problem.

I have no clue how to start solving this problem. Can someone maybe give me a hint?

----------

## NeddySeagoon

oz_tiram,

Share dmesg with us - via pastebin and 

```
lsusb -v
```

also via pastebin.

wgetpaste is your friend.

----------

## oz_tiram

 *NeddySeagoon wrote:*   

> oz_tiram,
> 
> Share dmesg with us - via pastebin and 
> 
> ```
> ...

 

Here is the output of dmesg:

http://pastebin.com/geEFuqeb

And here is lsusb -v

http://pastebin.com/brQqQ7d2.

I hope someone can make sense of this.

----------

## NeddySeagoon

oz_tiram,

Some details of your USB device tree.

Bus 002 Device 005: ID 0781:5567 SanDisk Corp. Cruzer Blade

    MaxPower              500mA

I actually wanted all of 

```
lsusb -v
```

so I could check for over current conditions. 

Your memory stick wants 500mA.  That's all the power a single USB1 or USB2 root hub is supposed to provide for all connected devices.

For USB3, the limit is 900mA.

We see its device 005. Device 001 will be the root hub itself, so there are another three devices connected.

Please pastebin all of  

```
lsusb -v
```

 (yes, its big). 

Please pastebin all of dmesg too. (yes its big as well).

There may be messages about devices being powered down, or whole root hubs being shut down due to power overload.

```
emerge wgetpaste

dmesg | wgetpaste

lsusb -v | wgetpaste
```

 and tell the URLs you get back.

----------

## oz_tiram

 *NeddySeagoon wrote:*   

> oz_tiram,
> 
> Some details of your USB device tree.
> 
> Bus 002 Device 005: ID 0781:5567 SanDisk Corp. Cruzer Blade
> ...

 

Here are both full outputs:

https://paste.pound-python.org/show/ls83Q9JEjCWivZrj78mE/

https://paste.pound-python.org/show/T1mBxQsclmhGhP9Do6vr/

----------

## NeddySeagoon

oz_tiram,

Thank you.

By USB Bus Order

```
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

Device Descriptor:

  bLength                18

  bDescriptorType         1

  bcdUSB               2.00

    MaxPower                0mA

Bus 001 Device 002: ID 8087:8000 Intel Corp. 

Device Descriptor:

  bLength                18

  bDescriptorType         1

  bcdUSB               2.00

  bDeviceClass            9 Hub

    MaxPower                0mA
```

That's a USB 2 root hub with a powered hub attached as device 002. 

There is nothing connected to the powered hub.

```
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

    MaxPower                0mA

Bus 002 Device 002: ID 0bda:572a Realtek Semiconductor Corp. 

Device Descriptor:

...

  iProduct                1 Lenovo EasyCamera

    MaxPower              500mA

Bus 002 Device 003: ID 8087:07dc Intel Corp. 

Device Descriptor:

  bLength                18

  bDescriptorType         1

  bcdUSB               2.00

  bDeviceClass          224 Wireless

  bDeviceSubClass         1 Radio Frequency

  bDeviceProtocol         1 Bluetooth

    MaxPower              100mA

Bus 002 Device 012: ID 0781:5567 SanDisk Corp. Cruzer Blade

  bLength                18

  bDescriptorType         1

  bcdUSB               2.10

    MaxPower              500mA

```

Bus 002 has your webcam, bluetooth and SanDisk Cruzer connected for a total load of 1100mA but the limit is only 500mA.

Its likely that thats the problem.

```
Bus 003 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub

    MaxPower                0mA
```

Lastly, you have an unused USB3 port.

The fix is probably as simple as connecting the memory stick to the powered hub.  The memory stick in a USB2 device.

It won't benefit from being on the USB3 root hub.

Plug the memory stick into another USB port.  Run lsusb (without the -v)

When its on bus 001 or bus 003 try it.  

All those 

```
evbug: Event. Dev: input7, Type: 3, Code: 58, Value: 35
```

dmesg entries in dmesg may mean you have some debug options on in the kernel.

If they don't go away, or there is still a lot of logspam, turn off the debug options.

Some interfere with normal operation.

----------

## oz_tiram

NeddySeagoon,

So if I get you correctly, you are saying: plug the USB in a different hub, then it should work.

What I don't get is, why is there is an hub powered off:

 *Quote:*   

> Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
> 
>     MaxPower                0mA 

 

Is this the root cause?

And indeed, there is a third usb plug where the USB is detected. Some of these SanDisk USB Sticks are

detected on a third USB port. I can only see them with fdisk -l, after a while.

But they still won't autoatically mount. And when I do mount them with root and try ls -l in the mount location

the terminal will hang for a long while until it will first give an output. This is all so weird with these disks.

One more thing I don't get is this: other USB sticks (but not any of the SanDisk cruser blade) will mount.

So this means these USB sticks are trying to consume too much power while others aren't? 

Do you have any other  advice here?

----------

## NeddySeagoon

oz_tiram,

That's not powered off. MaxPower is the maximum current the device will draw from the bus.

By definition, root hubs are always 0mA.  They power other devices.

Devices powered by a mains adaptor are zero or very low. For example, a USB hard drive with its own power adaptor is usually 2mA or less.

With 500mA available for oll devices, bus powered USB hard drives have always been a bad idea.  The Y cable supplied by some was an attempt to get around the bus power limitation. 

Connect the memory stick to another bus and check that with lsusb.

Each USB bus may offer several connectors.

----------

## oz_tiram

eventually, this problem only happens with a certain type (Sun Disk Cruser Blade) of USB.

I gave up of trying to figure this out. Other usb just work on all ports of this laptop.

Thank you for helping me with this.

----------

