Your description does not make sense. A raid consists of at least two drives, so if you only have two drives in the system, one can not be part of a raid and the other not. Please try to provide a better description, as well as the output of lsblk.
** Changed in: ubiquity (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1409556 Title: RAID drive not seen by installer To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1409556/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs