I have much the same problem. Set up 4 pairs of raid partitions. After 'configure raid' get the error message "could not stat device /dev/md/4 (sic!) - No such file or directory. A re-boot gives message that md partitions are in safe mode. The installer has a bug.
-- configuring raid during installation failes https://launchpad.net/bugs/95704 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
