PR4100 with USB Dual Dock, Can't See Both Drives

Hi all,

I’m trying to connect a dual drive dock via USB and it works fine but I can only see one drive of the 2. Is there any way to manually mount the other drive maybe? Or another way?

I’m sure is working correctly and the drive must be unmounted. It only activates one share in the control panel.


Normally Dual Drive Docks have the a Drive on LUN0 and the 2nd one on LUN1.
My Cloud doesn’t support a USB drive on LUN1.

Enable SSH and follow the steps in the article below to see if the device is on LUN1 or not.
Check the Logical Unit Number section

External USB Drive Will Not Mount, Not Seen or Detected by a My Cloud

Answer ID 18918

Thanks. I don’t have that error that you mention, I can see one drive and it has its own share, but from the SSH I can see the other mounted drive but it doesn’t create a share for it, just for one of the two. I can see the other if I disconnect one, but it disconnects again if I plug it again, so it’s always one.

There’s 2 of 4TB drives

Ahhhh the 2nd share may have the same name as the 1st which is not supported. Try renaming the 1st USB stare and reboot. The 2nd usb share should show up.

No luck. I can manually mount it and see the contents in SSH, but no share. They appear like /dev/sde1 which is mounted (/mnt/USB/USB2_e1) and with share and /dev/sdf1 which is not.

would like to know what the limitation is about.

USB hardware controller implementation, or My Cloud OS ?

Disappointed about this. An 8 year old macbook pro sitting on my desk can see the individual drives inside a OWC Mercury enclosure when the enclosure is set to INDEPENDENT mode, but a 2 year old EX2 Ultra doesn’t.

The only limitation in My Cloud OS 5 is that two SAMBA shares cannot have and identical name.
If /dev/sde1 is mounted and the share name is “USB Drive”, and /dev/sdf1 is mounted and attempts to have the same SAMBA name of “USB Drive”, then the 2nd drive will not not have a share created because it would have the same name.

I am using AFP to connect to the Shares my EX2 Ultra serves. Upon formatting the 2 disks in the enclosure (each one using a different file system), they appear/mount independently on my macOS desktop.

when i connect the same enclosure to the NAS, it shows me only the disk in bay 1. if bay 2 does not appear, there is no share associated with it in the USB list of devices connected.

it would have been nice to have both drives appear via that single USB connection. Unfortunately I need to now use the 2nd USB port if I wanted true independent USB shares for each drive.

I’ve changed the share names, when disconnecting one and connecting the other, different share names appear. Still, both won’t work. I don’t see any useful log either about anything happening.

my independent disks are also using unique names. the my cloud OS is seeing the identifier/name of the enclosure, not the disks.

Please collect the system logs and send to support with the make, model and format of your external USB drives.

How to Collect My Cloud System Logs

Answer ID 18374

I am also very dissapointed about this Bug since it also wont work with Western Digital’s Own Products. I did try to connect a WD MY Book DUO which is configured for dual disks/volumes. And only the first Disk is shown. This should be recognized as a issue/limitation and improved. I am sure that many of the wd NAS owners also own My Book Duo devices… and would be very happy if they could use them nicely.