I had a threee disk unRAID system up and running and just added a third data drive.  It was a drive previously used in another server so it had data on it which I didn't care about.  Anyhow, I added that drive to the array and powered up the system and all the drives had a blue dot next to them.  I would have thought that only the newly added drive would be blue, and the rest would be red.  This made me nervous beacuse I had to the hit format button blindly.  It performed everything correctly, but it would be nice to have only the new drives be blue and the rest some other color so users can be asured that unRAID still recognizes all the previous drives and won't format any of them.

I guess this isn't a problem after all and I must have done something wrong.  I installed another new drive (re-used with data on it) and it acted totally different.  This time it booted up and started the array as it was before I added the drive and I had to stop the array, assign the drive to the array, and all previous drives were red and the new one blue (the last time the array was stopped and all drives were blue).  It's even clearing the new drive this time, whereas the last one it never did that and just formatted it.

 

In another thread with a similar problem JoeL said he's only ever heard of all blue indicators when unraid has been shut down properly and it's unsure of parity.  I cold have sworn I shut it down properly the last time, but maybe I'm wrong.  Anyhow, I have a bunch more drives to add so I'll continue to monitor this situation.

Although I did just find this inconsistency.  A green light and it's unformatted?  There seems to be some kind of bug.

 

...Or I don't understand the indicators properly.

Although I did just find this inconsistency.  A green light and it's unformatted?  There seems to be some kind of bug.

 

...Or I don't understand the indicators properly.

I think the green light indicates that the unformatted drive is now part of the array's parity calculation.  It has been cleared and ready for formatting.  If it were to fail at this point in time you could concieveably replace it with a new drive and the array would be able to reconstruct it from parrity as a completely cleared drive.  (and still unformatted)

 

After you format the new drive you will see that roughly the same number of writes to it to format it are also counted on the parity drive as it records new parity records for the blocks on the new disk being formatted.

 

You are correct in one thing... A good, complete, clearly written description of the colors of the lights, and how they will appear in various situations is sorely needed.