I am sorry if this has been asked a hundred times before but I have tried searching and haven't seemed to be able to find an answer.  I have had my unraid server running for a few months now and everything seemed to be working as intended in regards to high-water splitting files evenly across disks.  Lately I have noticed though that when I write data to the array it seems to want to put everything on to disk 1.  I can force it to write data to other disks if I disable those disks from the share but obviously that is not ideal and I am just curious as to why this is happening or if I am misunderstanding something.

 

I've attached images of my share settings, and also of my disk usage settings.  As you can see it was clearly working at some point since the 16tb drives were filled up to the halfway point.  Should I just ignore this? Seems odd to me that it's not writing data to the rest of the disks in the array and defaulting to disk 1.

 

 

Writes go to disk 1 until it has 8TB free.  Then disk 2 until 8TB free then 3 until 8TB then 4 then 5

 

After that, it does disks 1,2,3,4,5,7,8 until 4TB free

Then all the drives in order until they all have 2 TB free and so on

 

In your case all the 16's have less than 8TB but still more than 4 so writes go to disk 1 until its 4TB then disk 2

 

IE: high water is NOT 50%,25%,12.5% etc free of the individual drives capacity.  It's calculated based upon the largest drive.

Ah thank you, that explains it.