Sharespace 4TB Raid-5 volume degraded

[acidrop]

Hello

I have a WD Sharespace 4TB NAS with 4 x 1TB in RAID-5 with WD Green Hard Disks.
Recently i saw a blinking orange led. I've logged in web interface and went to

disk manager.There I can see all 4 disks in Good Status.HDD4 reports Unassigned.
Next to it  are  2 options 1. Safely remove disk 2. Clean Disk

Should I proceed with one of these options to rebuid the array or should I do it through ssh with mdadm?

Thank you

[Wizer · Accepted solution]

yes you can try to clean the disk..

Be careful when doing ssh.. if you are familiar with the process then it will be up to you

[acidrop]

ok i've backed up everything and cleaned the disk.

Now disk shows as "new".Then i go to volumes and raid management 

and i have an option to "add".When i press it it shows only this disk in "span"

configuration.I think it is trying to create a new volume on this one only.Should i

choose that or "modify" current raid5 volume and press "submit"?

On this one it says that "This process will erase all data in the volume!" and i don't 

want that! I just want to add this new drive to the volume and rebuild it without loosing the data.

Is that possible?

Thank you

[acidrop]

Update:

Ok I just rebooted the device and now it shows status "recovering" without doing anything let's see what will happen...