Sun Thumper X4500 Documentation
Disk physical layout
Remember that only 2 disks out of the 48 are bootable. When all slots are filled, these disks are sdy and sdac, both connected to controller 3. See the graphical layout picture for an idea wher to find your disk.
More documents on how to potentially configure a Thumper may be found at the NDPF file area for X4500.