Connecting external USB 3.0 2-bay dock to MyCloud EX2 Ultra - only one drive is mounted

I have 2x3Tb WD Red NAS drives in the external USB3.0 dock, both formatted with xfs, but only one is visible when connected to MyCloud EX2 Ultra. Is it by design? If it is not, any chance I can see both external drives mounted automatically without getting into ssh/mount it manually?

Thank you!

PS - I have tried two different docks, still can see one drive only in MyCloud. When I connect the dock to my Ubuntu box I’m able to see (as sdd1, sde1) and mount both drives.

PS2 - Just tested - when I do connect both docks with one drive in each dock, MyCloud is able to mount both external drives automatically.

Hello,

The manual says that You can attach a powered USB hub to the external USB port and attach up to seven
USB devices to the hub.

I recommend you contact WD support for assistance with this issue.

any updates here? i also have the problem, that only 1 of 2 HDDs in a HDD Dock are mounted. The Dock is powered and holds 2 HDDs which are plugged in in the EXT2 via an USB3 cable.
i can mount the second drive via ssh but it isn’t recognized as share in the web control panel.

Any updates on this how to get the second drive mounted?