I added two 8TB disks to my Ubuntu system and modified the BIOS to use Intel RST. In Ubuntu the two disks showed up as part of a RAID array, in the fdisk they show up individually as sda and sdb, but as part of a RAID array. I formatted each independently. After not being able to mount them, i switched the BIOS to ACHI. The two disks still existed as a RAID array within Ubuntu with the ACHI setting.

After read error my ubuntu server couldn’t load up RAID 1 – 2 drives.