Drive failed or not?

So this morning copying a couple of video files to my WD mirror drive (2 x 6tb)

copy failed

drive disconnected.

i looked into control panel and had warning about 1 drive having failed.

Rebooted mirror, now it says its ok.

confused

ssh in and run a chdsk, I would just to make sure, . the notification might have been that it was out of sync and failed etc… im sure if its running now its fine. Drives usally fail when they fail from my exp…

I am currently running the full system test which has taken several hours and probably another few more hours to complete.

What I dont understand is now my disks (after the reboot) show as healthy but raid status showing as degraded.

Once the disk test completes I guess I will know more.

Are the drives almost full?

No only 2/3 used