I had a set of four old 4TB drives sitting around, so I bought a few enclosures and a hub so I could build an OMV NAS from a Pi 4 for experimentation. I can see all four drives in the Disks page, and was able to wipe all 4, and in the File Systems page I was able to format them all as EXT4. After formatting though only one drive at a time will show up in the File Systems page. If I mount it, it will show me another disk as unmounted. When I try to mount that one it refreshes and shows me the disk I had originally mounted as mounted.
I suspect that the issue is the enclosure (https://www.amazon.com/gp/product/B01JNLCC7U/), because it shows all four drives as having the same serial number. Can anyone confirm?