I have two WD3200AAKS-0 disks in a RAID1 array.
After a recent power failure, Volume1 (there is only one) shows status Degraded , but bootable.
As physical drives, one shows "Member Disk(0), the other shows "Error Occurred(0)".
I have the option during the boot phase to <CTRL-I> to enter the Configuration Utility.
Have I got a dead disk?
What might I do in the Configuration Utility?
Just initiate a rebuild, but to avoid user mistakes get all data off first to a backup.
The rebuild can be done in Windows (with Intel RAID controller utility) or after the POST (Power-On Self Test) when you hear the beep and the it tells you to press CONTROL+I for RAID setup. There should be an option to enable rebuild on the volume.
But you should be able to use the volume per normal; and boot with it. Degraded means you still got enough disks to access all data on the RAID.
PS. You may want to consider using a real backup instead of RAID1; RAID1 cannot replace a backup, though both cost the same disk space. So my advice would be: split the RAID and use one disk as backup instead, preferably in another system for optimal security, and use network (LAN) backup software.
I have in the past had discrepancies between the two disks, and have seen them being brought back into agreement, from a display in the task bar. I thought it would happen again that way, but it's not happening. Maybe the INTEL Raid utility has got itself scrubbed - I had a power failure a few weeks ago which did all sorts of damage.
How might I check the presence of the Intel Raid controller?
How might I reload it if it is not properly installed?
I do also back up to two USB connected disks (one of which is usually off site), and some data is also kept on a RAID1 NAS - you can't be too careful - but maybe I'm just paranoid!
If I understand you correctly, I can also rebuild the dud disk via the CTRL-I on boot up. But I'd like to reinstate the Intel method if possible.