Mac OS X Server: Starting Up Mac OS From A Separate Disk

This article tells how to start up a computer from a separate hard disk containing a different version of Mac OS (such as Mac OS 8.5) when the default hard disk has Mac OS X Server installed and is the default startup volume.
To start up the computer in Mac OS 8.5 instead of Mac OS X Server, hold down the Option key while the computer is starting up. Mac OS 8.5 must be installed on a separate drive or partition, and that drive or partition must be selected in Mac OS 8.5's Startup Disk control panel.

Published Date: Feb 18, 2012