[G4] Can't startup in Single User mode

[Perry The Cynic]

--On Sunday, May 22, 2005 5:00 PM +0200 ksimones at spymac.com wrote:

> (I posted this on the x4u list also.)
>
>
> Hello all.
> I'm posting for a friend who can't startup in single user mode and I
> don't have any answers for him. I thought he may have a bad keyboard, but
> he tried a new one and still doesn't work (cmd+s during startup).
>
> [...]
>
> Any help would be greatly appreciated. It's strange that such a basic
> level task can't be done on his machine.. One thing I just thought of and
> haven't suggested to him is to reset the system via the CUDA button or
> remove the battery. Is there anything anyone can think of for this one?

Well, you should reset the PRAM (aka Open Firmware), of course: reboot, 
hold down Cmd+opt+P+R, wait for restart chime, continue holding for three 
cycles, then let go. [The three-cycles thing is probably no longer 
necessary, but it was needed on old(er) Macs, and has become something of a 
magic incantation. Can't hurt, anyway. :-)]

If your OF parameters are set weirdly, you can get all kinds of strange 
behavior. The reset should clear all such state back to the defaults.

Another try: Reboot, hold Cmd+Opt+O+F. This should get you into the Open 
Firmware prompt. If *that* happens to prompt for a password, you've got OF 
security enabled (that's one reason why single-user booting may not work). 
But switching the RAM should have reset OF protection already...

At the OF prompt, typing reset-all<return> should also reset everything.

If you can get to the OF prompt at all, you can also explicitly request 
single-user boot by setting the boot-args variable to include the string 
'-s'.

Cheers
  -- perry
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Perry The Cynic                                             perry at cynic.org
To a blind optimist, an optimistic realist must seem like an Accursed Cynic.
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