Union File System not balancing across array

Maybe a configuration problem but I have a UFS volume over a snapraid array where a file system on one of the drives in the volume is indicating "disk full" when I try to copy a file to a directory but there should be space in the UFS volume. When I do a df on the UFS volume the size looks fine - have 8TB free - but when I check the actual disk that contains the directory I'm copying to it's at the limit I configured for UFS to not write to the drive 4G so nothing can be written to it.

When I check the UFS configuration in OMV the create policy is set to existing path, most free space. The other disks in the array all have space available - hundreds of gig. I'm at a loss what else to check and what to do to fix the problem so I can use the available space.

Basically I need to find out where to look to configure UFS to allow the spreading of files across all the volumes of the array.

Here's my UFS config at a high level:

UFS_Filesystem :

/dev/sda1

/dev/sdb1 ---> full disk less 4GB configured as limit

/dev/sdf1

Thoughts?

It does not! Bingo something to try out and now that you mention it that makes sense, how else would the volume know where to put files... I'll apply the "fix" and provide status... Thanks for the guidance.

gderf - Your recommendation was the fix to the problem. I created the directory I needed on one of the other drives and it worked flawlessly. Thanks! Now I know how to set up my drives for future using this config - I'll also read up on the other options to see if any fit my setup better.