How should i upgrade drives in Raid 1?

So, I currently have two separate RAID 1 Volumes.

2x2TB Drives in Raid 1

2x4TB Drives in Raid 1.

I want to buy two 8TB wd reds and replace the 2tb drives.

Here’s where it gets interesting. I want to put the data from the 4TB’s on the 8TB drives, and the data from the 2TB drives on to the 4TB drives.

I don’t know the best course of action to accomplish that.

A few ideas i have are

  1. Replace the 2’s with the 8’s, create the raid, transfer from the 4’s to the 8’s. clear then 4’s. then via a PC, transfer the contents off one of the pulled 2’s onto the now empty 4’s?

  2. Pull a 2, put in an 8, populate the 8 with the contents of the 2, then replace the other 2 with an 8 and finish the mirroring. Somebody said this wasn’t possible? but i don’t know.

  3. pull a 2, replace it with an 8. create a seperate (Third) volume, move files from 4 onto 8, then 2 to 4, then pull the remaining 2, pop another 8 in, then combine the two 8’s into a single Raid 1 volume? Not sure if possible.

  4. a better idea i’m not aware of.

Any help would be greatly appreciated. Thank you.


I would recommend you to contact the WD support they will help you in this matter because at the last data is important.

back everything up on a different system and do what you need.