I've restarted my server several times this evening, working on some various things, and the last time I restarted it took forever to start.  I noticed an orange triangle as the icon for the server tab, so I looked at the array devices tab and saw disk 5 has a red x next to it.  I stopped the array to see if the disk was missing, but it showed the correct disk listed, so it's not missing.  I shut down the server and made sure the cables were all well connected (they were), then restarted.  It's still showing the red x and shows the disk as emulated.

 

I'm not sure how to fix this now.  I've attached the diagnostics file, but I didn't see anything obvious in it.  I appreciate any help in resolving this issue.

media-diagnostics-20160120-2138.zip

You get a red 'x' against a drive if at any time a write to it fails.  From that point on unRAID stops updating the physical disk and only writes to the 'emulated' disk.  The only way to clear this status without potential data loss is to rebuild the disk.  This can be either onto a replacement disk, or if you think the disk is actually OK and the write failure was an external factor you can rebuild the disk back to itself.

 

If you wanted to try and re-use the "bad" drive you can do this:

1. Stop array

2. Yank bad drive (or just unassign it)

3. Start array

4. Stop array

5. Reinstall bad drive (or re-assign it) - unraid will "think" this is a new drive because step 3 erased disk-id of that bad slot

6. Start array - this will trigger a rebuild