Software RAID confusion after inserting third disk
 

Hello,

I have just installed Debian on a software RAID system on two new disks and everything works fine. My problems start when I try to plug in my old disk to transfer my old data to the new system. During the boot it complains about missing resume file and failed filesystem check and send me to single user mode.

I'm not 100% sure whats going on, but I was thinking perhaps my old disk is named sda so that it messes up the RAID setup? I don't know why this should happen since I have my new disks as SATA Master 1 and 2 and the old disk as SATA Master 4, but I'm no expert in these matters...

Another thing that confuses me a bit is why Grub doesn't have any problems booting if my old disk is set as sda.

I would very much appreciate some advice here.