This page is to collect tips and tricks for when you are confronted with a stone cold dead Unix box. By `dead', we mean ``won't boot at all''; at best, you can manage a very lame single-user shell. More likely, you're looking at a chat with your boot firmware, or PC BIOS ...

For a Sun, the "Sun System Handbook may give a full run-down on the Open Boot PROM commands (depending on whether you have full access or not). Of note: holding down STOP-D ('STOP' and 'd' keys at the same time) while powering up gives you a ``diagnostic power on''. You may want to do this before a Sun engineer asks you to :-)

Note: POST == `Power-On Self-Test'.

If you have an apparently dead disk on a Sun, a couple of things to try:

If SCSI disks, you can try the PROM command probe-scsi-all.
For any old disks, you can pop in the Solaris install CD (the ``Software 1 of 2'' one), do a single-user boot from that with boot cdrom -s, then type iostat -En.

Memory checking: If you're worried about duff memory [or CPU] on a Sun, you can download and run a stress-test package called SUNvts, available fromr SunSolve, or in the Solaris 8 CD pack.