A good references:
 http://www.squirrel.com/sun-nvram-hostid.faq.html

1. Setting the HostID and mac address in eprom

mac address: 00 80 B6 00 4F 82
hostid: 80084555
machine type: 80 (for LX, 4, 5, Ultra1).

To show the contents. 
	.promid  or banner

Need to write the information into the first few byte in the PROM using mkp.
At the OK prompt do this: 

	1  0 mkp 
	80 1 mkp
	00 2 mkp
	80 3 mkp
	b6 4 mkp
	00 5 mkp
	4f 6 mkp
	82 7 mkp
	0  8 mkp
	0  9 mkp
	0  a mkp
	0  b mkp
	08 c mkp
	45 d mkp
	55 e mkp
	0 f 0 do i idprom@ xor loop f mkp

2. Set the boot device.

Bigdog boot from SCSI address 3 ,or c0t3d0s0
At the ok prompt, do this:

	setenv boot-device disk3

'printenv' to check

3. booting troubles.

On 2013.08, hilodog did not comeback after a reboot.

To view consult ouput connect to serial port using 96008N1 or you
can use mako-spare+minicom to view serial. Could not send break to
get OK prompt.

Stuck on  waiting for 'ARP/RARP'. Need to connect to a PS/2 Keyboard.
Cntl-Break on PS/2 keyboard got me to the OK prompt.
Type 'boot disk' at the OK prompt to boot the disk.