Mac|Life – All Articles
by Cory Bohon
Occasionally your Mac may refuse to boot due to any number of problems; however, you can still get to your important files so long as your hard drive is still intact. To do this, we’ll use a little-known boot utility called Target Disk Mode. Using this mode, you can connect your misbehaving Mac to another Mac and use it as an external hard drive, allowing you to retrieve your files and stow them at an alternative location.
What You Will Need:
>> Two Macs with FireWire or Thunderbolt Ports
>> FireWire or Thunderbolt Crossover Cables
1. Connecting Your Macs
You may have a FireWire crossover cable lying around if you have an external FireWire hard drive or other FireWire peripheral.
Connect the computer you will be transferring files from (the host) to another Mac (the recipient) using a FireWire crossover cable. This crossover cable has two male FireWire connectors available in the flavor your machines accept (either FireWire 400 or 800). If one computer has FireWire 400 and the other has 800, you will need a FireWire 400-to-800 crossover cable. Cables like this can be readily found online or at your local electronics retail store. If you are using newer Macs with Thunderbolt ports, you can also use a Thunderbolt crossover cable to conduct the file transfer.
2. Enabling Target Disk Mode
When you see the FireWire logo, it means that your host machine is acting as an external FireWire hard drive.
After connecting your computers through the FireWire crossover cable, shutdown the host computer and restart it while holding down the “T” key. After a few seconds, the recipient computer will mount the host computer as an external drive and will appear in the Finder; while sharing, the host computer will display a FireWire or Thunderbolt logo on the screen.
3. Transferring Your Files
After the host computer appears in the Finder, click on it to begin transferring files.
After your host computer appears as an external drive, you will be able to navigate through the drive, and retrieve your important files. To access files in your Home directory, you will need to navigate from the root of the drive to /Users/YourUserName.
If you will be using the recipient computer full time, you can use Migration Assistant (located in the Utilities folder on the recipient computer) to transfer over all of the necessary files and user accounts from the host computer. This is a pretty straightforward process and the assistant will guide you through completing it.
Remember to properly disconnect your host computer to avoid any data corruption.
When you are ready to disconnect your host Mac, don’t just unplug the machine or turn it off. First, eject the disk in Finder, just as you would with any other external drive. After the disk is no longer visible in Finder, you can press the power button on the host Mac to turn it off.