WD Sentinel DX4000 4TB - drive expansion - 4TB drives

Dear WD Community,

I recently purchased a WD Sentinel DX4000 4TB (WDBLGT0040KBK-21) it is running at RAID 1 and offers 2TB of usable storage. I underestimated the growing demand of storage when I ordered the 4TB-Model. So I purchased 2 new 4TB-drives (WDBYBL0040HNC-EASN or HDS5C4040ALE630). I swapped out 1 drive at a time and let the System repair hoping that the usable storage would grow to 4TB. The next step was to completely rebuild the System (factory reset), however even after the rebuild the sentinel only offered 2TB of usable storage.

Can someone help?

If you will open the dashboard on the server, click on Monitor, on the right is a link that lists comapatable hard drives and a button to go to the WD store to get them

The drives that I purchased are listed in the “Compatible Hard Drives for WD Sentinel DX4000” document. The Sentinel recognizes the new Drives and builds the volume (Raid 1), however only 2TB of usable storage (using 2 x 4TB Drives at RAID 1) is available.


So now you only have the 2 new drives in the box?  And the original 2 are sitting on the shelf?

Attach the new drives to a working box and do diskpart to celan the drives making sure you clean the correct drive(s)

Put them back in the wd b ox and run the middle step, recreate my storage.

When that is done look at the log file in the wd folder of the thumb drive and see what it says.

If it looks like what you want then do the 3rd step recover my server

It would have been much cheaper to pucrchase one 2tb drive to get to 4tb , than to purchase two 4tb drives to get to 4tb ???