I’ve added the second drive & tape backup to my Linux box today. I still haven’t been able to get RAID fully working.
I’m setting up the drive as RAID level 1 with my existing drive and I’m able to get the new drive to be recognized and created a RAID array containing that one drive with the old drive marked missing. I’m even able to start it and have it recognized automatically or mount it. If the partition type is NOT raid autodetect (FD), I’m even able to boot from that drive but the RAID device won’t work. If I set the partition type for autodetect, it’s recognized by the kernel and started, but I get a kernel panic when it tries to mount that filesystem.
UPDATE: I got it working. I had to specify root=/dev/md0 on the kernel boot command line