I have a SANS DIGITAL TowerRAID TR4UT-B setup in RAID5 that I originally had connected to my Windows 10 PC (formatted NTFS). I wanted to just move it over to unraid as an unassigned device to handle items that I didn't want on the array.
It shows up as an unassigned device in unraid when I plug it in, but I guess it doesn't detect the file system. It'll only let me format it, not mount it. It looks like it's showing the correct size though as 6TB (4x 2TB in RAID5). I know the NTFS filesystem is intact. If I plug it back into my Windows 10 machine, it comes up fine. The raid controller is also built into the TR4UT (not using one on my Windows 10 PC for example). Not sure what to check first here, I thought Unassigned Devices could mount NTFS.