I need to startup from an external CD ROM attached to a PPC 6100. It's running 8.6 with a G3 upgrade card installed. The System Profiler recognizes that it's attached, but when a CD is inserted, it doesn't mount, otherwise, I'd select it from the Startup Disk Control Panel. I'm trying to solve that problem by finding and replacing the drivers -- no luck yet. The setup and drive had been working fine for nearly a year, but suddenly stopped. It could be that it's old and finally decided to die, but I'm not giving up yet. I'm hoping that it's just corrupted drivers.
Holding down the "C" key will not work since it is an external CD drive, but I know that there is a key combination that could be held down at startup that would force the Mac to boot from another startup disk. Does anyone know what that combination is?