For testing purposes I frequently want to restart my iMac in El Capitan, Sierra, or High Sierra which I have on separate disk partitions. When using System Preferences/Startup Disk, I have to enter my password to do that. Is there any way to avoid this requirement?
You can press the Alt-Key on startup to choose from the different booting devices... So you can just restart the Mac and when it "chimes" hold down the alt-key until you can see the partitions.
If you were searching another way, ask again... maybe you could turn off the password protection via System Preferences>Security>More Options>Systemwide... but I can't test it right now, I am sorry
- Restart and press the Option-Key during startup
- Choose your Startup disk from where you want to make it as startup disk
- Hold down the Control-Key the Arrow on the chosen disk turns in a Circle.
- Click on the Circle to make this startup disk permanent.
Note:This Option not work on all Systems and Configurations. I've tested this with Sierra on iMac Late 2015.