Background

Rebuilding a RAID1 mirror with a Truecrypt container on it may require some additional steps. I guess that since no filesystem is visible on the disk, the RAID array is having trouble determining which disk to rebuild from. If your neighbourhood have had a blackout, the filesystem in the container is probably dirty anyway. This is how I take care of the matter on my external ICY Box IB-RD4320 USB chassi.

The manual for ICY Box IB-RD4320 USB chassi have this table regarding the meaning of the LED lamps on the unit: