Here’s how to make a Mac start up disk image using Disk Utility:

You can image an active boot drive, but try to stop or quit any services and applications to make sure there is minimal writing to the hard drive while the image is being created. It is best to create an image from a drive that is not booted at the time. We’ll talk about the GUI disk utility version first, and then we’ll discuss the CLI and automated version. There are two ways to create these images: Using Disk Utility or using the hdiutil and asr commands in the terminal. You will need an additional volume or a mounted shared drive with enough space to create the image. This image will be compressed and will make recovery fast and easy. This how-to will show you how to make an image of one hard drive and store it on another drive. It’s an indispensable tool – one which could save your data and prevent a lot of headaches down the road. If you’re into preventative maintenance and creating backups like we are, you’ll need to create a Mac start up disk image. AirPort Apple Apps Backups Developer Education Email Hardware Internet iPad iPhone Mac Music Network Photos Security TV Weekend Wonk

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