Booting off a Secondary Harddrive

supanatral · #1 June 15th, 2007, 11:49 AM

I suspect that the hard drive in my notebook is bad and causing it to be unstable. So far I replaced the Ram, the motherboard and I know it won't make a difference but the top panel of my notebook has also been replaced (for a totally different reason). Long story short, it's still freezing on me.

Apple did me a favour and replaced the motherboard even though they weren't able to reproduce the issue, but they can't continue replacing parts under warrenty if they can't reproduce the issue. So I ended up having to buy an external hard drive to boot off of instead.

The quesion is this: If Mac OS X needs to use virtual memory will it use my primary hard drive inside the notebook? or will it only use the external hard drive?

**fryke** · #2 June 15th, 2007, 01:54 PM

It'll use the system volume by default. If that's the external, then it uses the external.

supanatral · #3 June 15th, 2007, 02:18 PM

I'm not exactly sure I completly understand. So just after I turn the notebook on, I push and hold the option button, and boot off of the external drive. Does it then use the external drive for virtual memory? if not then how do I make my external drive default?

**fryke** · #4 June 15th, 2007, 05:13 PM

Okay. Let's put it this way, then:

System A is installed on your internal drive (volume A). Booting from system A uses volume A for virtual memory.

System B is installed on an external (or secondary internal) drive (volume B). Booting from system B uses volume B for virtual memory. Per default, your system will *always* use the volume you _boot_ from for virtual memory. The (active) system volume.

After you have successfully booted into _any_ system volume, you can use the System Preferences' "Startup Volume" preference panel to set the startup volume for future reboots.

one1step1 · #5 June 16th, 2007, 09:45 AM

To clone that drive, you probably want to use 'Super duper', since the cloning portion is free. Although.. it does sooo many other things, it's actually worth the price.
Super Duper

supanatral · #6 June 16th, 2007, 04:37 PM

Thanks Fryke, that makes sense.

I've already used Carbon Copy Cloner to do that. I gather that Super Duper is probably better then CCC but when I did research, I couldn't find the difference. Does anyone else know what the differences are?

**fryke** · #7 June 16th, 2007, 05:53 PM

One costs money.