I have an external 500Gbyte USB drive that I want to use for back ups. Ideally I'd like to store an ISO image of my desktop and laptop, but you can't create an image from a startup disk. So I'd like to see if there is a way to make the USB drive bootable.
hunterrose30
Favorite Answer
You can create an image using disk utility. In your case, boot off the disk that came with the computer by holding down the C key, have your ext drive connected to the comp, instead of installing the software, go to utilities, in there is disk utility. Click on your HD, click on new image, save it to your ext drive as read only and no encryption.
Takes maybe 15 mins max to make a HD image of your Mac.
Restart the comp, go to sys prefs, click on startup disk, choose your ext drive. Not positive, but you should be able to boot off it. Regardless, you now have a full image of your HD in case it ever dies.