Adding a 12TB HDD to a Nas DS418

I bought this NAS back in November 2022 and at the time I bought a single 4TB drive to put in the Nas. At the time I watched the YouTube video on how to set it up and it’s been running great since then. I just wanted to upgrade the storage and take the 4TB out of the Nas since each bay can hold 12tb. So I bought a 12tb. But I just don’t know how exactly to add it to the Nas. I have everything backed up on a 1tb external drive so I won’t officially lose everything. But I just don’t remember which type I used whether it was raid.

You can open Storage Manager from the DSM desktop. Under Storage Pool, it will tell you your current pool type, like SHR (most likely since it is the default), Basic, or something else.

On a side note, and with all respect, your post surprises me that you seem to be happy without drive fault tolerance while having one disk in a 4-bay unit. And, you upgrade from 4 to 12TB disk while having backed up everything on a 1TB drive. I would only add a second 4TB disk for fault tolerance and live on much happier.

I meant to say that I have 2tb external and I only have about 1 tb worth of stuff on there right now and I’m adding more overtime so I’m replacing the 4 with a 12 so that I can just buy more 12s and not spend money on 4’s that I’m eventually not gonna use. When I can replace the 4 with a 12 and have it backed up on externals in the meantime till I add another 12. And take the 4 tb that I can’t return and put it in my pc so it doesn’t go to waste. So tbh I’m helping myself long term. When I bought the Nas I just didn’t have the money for a 12 at the time. So I bought the 4 to only hold me over. With the full intent of replacing it and not buying another 4