I have 4 unused disks I've just inserted in my FREENAS-CERTIFIED-2U-12
- go to Storage > Pools
- click Add
- chose 'create new pool'
- it detects the 4 available disks, yielding Image1.png
- checkmark a pair of equal disks
- click the right arrow to add them to the first vdev
- click the "Add Data" button to add a secend vdev
- checkmark the other pair of equal disks
- click the right arrow to add them to the second vdev
- so far so good, yielded Image2.png
- now, click the X button of the first vdev
It now shows, in red, a strangely worded error message:
"WARNING: Adding data vdevs with different numbers of disks is not recommended. First vdev has 0 disks, new vdev has 2."
There is no "first vdev", I just deleted it!
(2) The "Estimated total raw data capacity" still shows 4.54 TiB, which doesn't make sense after the removal of the first vdev.