I'm new to solaris. Even if the os is not loaded, can we get OK promt via console?
Yes, you can, openboot is seperate from any OS loaded on the system. Hard drives needn't be plugged into the box at all.
Note, this is only relevant on sparc-based systems. If you need more info, list the system type.
Thank you. Ok prompt works from RAM or sun has any special device for it?
see the OBP like the BIOS on x86 computers...