In the "Disk Group Configuration(Automatic)", you can specify the number of drives to be 2. This will limit the LUN to use only 2 drives. Regarding "Auto Config Mode"  not being forgiving i.e. to ignore if not applicable to the server/controller, let...

"Auto Disk Selection" will work in this scenario with certain conditions. The disk selection will happen based on the available disks. UCSM will select the first available set of disks for LUN creation. So, if the server has only M.2 controller with ...