Comment 2 for bug 917520

Sergey, thanks for the bug report. I understand that this seems too harsh, but we are being perhaps overly careful not to boot up a system with a broken array unless the user explicitly allows it.

Answering the debconf question to boot degraded will solve this issue for you, as it trades the security of never booting automatically while degraded for the convenience of always having the system boot up.

Also I believe this is a duplicate of bug #872220