Upgrade from 2 bay to 4 bay

I just upgraded from a 2 bay mycloud EX Ultra to a 4 bay 4100, the old drives are twin 6TB setup as a RAID1 and I have 2 fresh 16TB that I would like to install and keep the data on the old drives so the files are still accessible and also be able to store data on the twin 16TB.

Is there a way to set that up - from what I was reading I want to do a RAID 10, but when I select the configuration it states that it would format the old drives.

Hi @kweskamp,

Please refer to the article How to Upgrade the Drives on a My Cloud Device (RAID Expansion):
https://support-en.wd.com/app/answers/detail/a_id/27421