Hi - We have 6TB on our Drobo 5D and bought 6 more TB. The new drives show up on the dashboard but do so separately ( not part of the same big pool). My understanding is that when I initially started using the Drobo I needed to set the drive allowance to reflect the largest volume it might some day be…and since I did not…the new drives cannot join the one large pool.
So if that is correct that means the only way I can group the new drives would be to transfer ALL data off the original 6TB drives to a third, separate, external drive. Then reformat the entire 12TB of drives on the 5D and set the maximum drive allowance to the largest size. Then recopy the project data back onto what it now one single pool.
I’m sorry if I am now using the right terms but hopefully you get the idea…
We are on a PC running Windows 7 - USB 3.0.