I have a My Cloud 4TB Gen1 with 4.x firmware for several years now.
I had several My Book 4TB connected to the My Cloud over an active USB 3.0 HUB.
Please no comments on this setup, I know its not the ideal way to extend the capacity of a NAS but it worked flawlessly for years. And it suited my needs completely.
Lately I exchanged some of my 4TB USB drives with 8TB My Books of the latest generation.
And this is where the trouble began. After a few days of use I got file corruptions on those drives. Resulting in files and directories not being accessible anymore. Even WD Diag could not complete its tests on these drives anymore and reported them as faulty. I had to reformat these drives on my Windows PC to make them work again. (After reformat WD Diag completed extended tests withouth any issues).
I repeated this scenario one more time with the same result.
This leads me to the conclusion that My Cloud Gen1 can’t adress 8TB USB drives correctly and overwrites existing data with new data send to the NAS over network.
Yesterday I got a factory refurbished My Cloud 4TB Gen2 from WD with FW 2.x
This device works fine with my 4TB My Books but refuses to mount the 8TB My Books at all.
Log message looks like this:
Unable to Mount USB Device
Unable to mount the USB device (vendor: Western_Digital, model: My_Book_25EE, serial number: XXXXXXXX). Please check the USB device.
Tuesday, 16 July, 2019 22:19:42
So, am I correct to assume that the My Cloud Gen1/2 don’t support 8TB external drives?
What about the My Cloud EX2? I could get one for an interesting price.
I couldn’t find any reliable information about the max. supported drive size for external USB drives for the My Cloud devices. Maybe someone can help?