PR4100 Red drive light but no disk issues

I have a strange problem with my PR4100 which has 4 x 6TB disks setup in raid 5

Last week i had a red drive light appear on bay 3, and then i had a red light appear on bay 2.

The errors said disk failure. So i bought 2 x 6tb disks (all WD red drives).

I replaced just disk 3, rebooted and then the system must have rebuilt the raid i assume.

Disk 2 is now blue (without a disk replacement). 1 & 4 are also blue but disk 3 is still red.

The raid is good, all disks are good on SMART. I have completed a full system check, and a full disk scan. No errors come up, but the disk 3 is still showing as red.

I have attached some pictures to show the system (i tried to add 5 images, but because i am new it allowed 2 images). I would be be very grateful for any help with this.


You could refer to the following link: My Cloud: Solid and Blinking Red Power and Drive LED Status

I know this post is a bit old, but I had this issue as well and managed to get it resolved.
I will guess that your original config (before one of the drives failed) was RAID 5+Spare. That is how mine was configured. After replacing a failed drive, I had the same issue… disk status and RAID status was all healthy (after the RAID rebuilt itself), but still a red light under the newly replaced drive. Then I noticed that my RAID said only RAID 5 and the “+Spare” was no longer there. I did not want to blow away my volume and start over, but I thought that was maybe the only solution. So i clicked "change RAID mode then OK and the “configure RAID mode” screen pops up. Select RAID 5 and you will see that you can “configure spare disk”. So I chose that option, and sure enough, it looked like the Volume was going to rebuild itself, but it did not… and the spare disk was added to the RAID config and the red light changed to blue.
Hope this helps someone in the same situation.

Jackpot ! Thanks that did it. It has been red for months. Now blue.