When users run prtdiag -v on the Enterprise 450
fully configured with disks they  can only see a max of 4 disks e.g.

Disk LED Status:	OK = GREEN	ERROR = YELLOW
		DISK 18: [EMPTY]	DISK 19: [EMPTY]
		DISK 16: [EMPTY]	DISK 17: [EMPTY]
		DISK 14: [EMPTY]	DISK 15: [EMPTY]
		DISK 12: [EMPTY]	DISK 13: [EMPTY]
		DISK 10: [EMPTY]	DISK 11: [EMPTY]
		DISK  8: [EMPTY]	DISK  9: [EMPTY]
		DISK  6: [EMPTY]	DISK  7: [EMPTY]
		DISK  4: [EMPTY]	DISK  5: [EMPTY]
		DISK  2:    [OK]        DISK  3:    [OK]
		DISK  0:    [OK]	DISK  1:    [OK]      

From the OBP prompt:

ok setenv disk-led-assoc 0 x y
where x= 1 to 10 PCI slot where the lowest Ultrascsi cont is installed
where y= 1 to 10 PCI slot where the uppermost Ultrascsi cont is installed
				
For example, if ctrl cards are in slot 5 and 7 enter the following:
ok setenv disk-led-assoc 0 5 7

if there is only one ctrl installed in slot 5
ok setenv disk-led-assoc 0 5
ok reset
ok boot -r to take effect

Now run prtdiag -v

Disk LED Status:        OK = GREEN      ERROR = YELLOW
                DISK 18:    [OK]        DISK 19:    [OK]
                DISK 16:    [OK]        DISK 17:    [OK]
                DISK 14:    [OK]        DISK 15:    [OK]
                DISK 12:    [OK]        DISK 13:    [OK]
                DISK 10:    [OK]        DISK 11:    [OK]
                DISK  8:    [OK]        DISK  9:    [OK]
                DISK  6:    [OK]        DISK  7:    [OK] 
                DISK  4:    [OK]        DISK  5:    [OK]
                DISK  2:    [OK]        DISK  3:    [OK] 
                DISK  0:    [OK]        DISK  1:    [OK]