Just sharing a small snag when setting up a DappNode with this configuration.
It is working fine for me and really made an older P55 chipset with i5 CPU pick up some disk speed.
So I setup the Raid 0 array in the bios and proceeded to run the install off the USB. All ran smooth until I hit the install grub bootloader step. In the menu it finds the actual drives but not the RAID partition.
So I noticed in the prior steps the RAID partition was /dev/mp126 remember that.
Then choose manual setup with will prompt you with /dev/mp add whatever your system call your raid partition and grub should install fine. If you get it wrong grub install will fail.
Hope this helps someone.