How to Boot Mac to Target disk mode and Transfer Files?

By Vivian | Posted to Howto on June 29th, 2020 |

Summary: This post introduces Mac's Target disk mode, which includes what is Target disk mode on Mac, how to start Mac to Target disk mode, and how to use it for data recovery and file transferring.

What is Target disk mode on Mac?

Target disk mode is a boot mode that makes the target Mac's startup disk work like an external hard drive on another Mac computer. By connecting two Macs together with Target disk mode, you can browse and open your files stored on the target startup disk. It helps a lot when you need to rescue files from a Mac that won't boot.

Mac target disk mode

How to Start Mac to Target disk mode?

To get into Mac target disk mode, you can follow the following guide step by step.

1. Preparations for Target disk mode

Before you get into Target disk mode, you need to prepare those things in advance.

  • Two compatible Mac computers with Firewire or Thunderbolt ports. One is the target Mac that you want to transfer files from. And the other host Mac is that your files are transferred to.
  • A Firewire or Thunderbolt cable. Either a Firewire cable or a Thunderbolt cable is needed for connecting two Macs. A USB cable is not working for this.
  • Power charger. AC power source is necessary for MacBooks, in case the Mac runs out of power in Target disk mode.

2. Boot the target Mac into Target disk mode

Step 1: Connect two Macs both through the Firewire or Thunderbolt cable mentioned above.

Step 2: If your Mac is turning on, click the Apple logo and go to System Preferences > Startup Disk and click on Target Disk Mode to restart your Mac into Target Disk Mode.

If your Mac won't turn on right now, you can force your Mac to shut down by holding the power button, and then reboot Mac with the T key pressed.

Step 3: Then you'll see a  Thunderbolt or FireWire icon on screen, which means that the Mac is in Target disk mode.

Step 4: Wait until the host Mac detects your target Mac and recognizes its startup disk as an external hard drive.

Step 5: Then you can go ahead to copy or transfer files from the target Mac to the host Mac easily.

Target disk mode won't work, how to transfer or recover files from Mac?

Sometimes, you can't boot your Mac into Target disk mode, especially if you don't buy the right Thunderbolt cable. And if your Mac is introduced in 2018 or later, Target disk mode won't work either. You can't externally access files on Mac that is secured by Apple T2 chip.

Then, you'll endeavor to recover files from the Mac that won't boot with some applications, which iBoysoft Data Recovery for Mac can help with. With this software, all you need is to recover files from the Mac in macOS Recovery mode and then backup data to an external hard drive, pure and simple.

When to use Mac's Target disk mode?

Then, what exactly Target disk mode is for and when you should take advantage of this mode?

  1. Transfer loads of files from one Mac to another.
  2. Migrate your data from old Mac to a new Mac.
  3. Access the startup disk's data when Mac won't boot.
  4. Recover or get files off the problematic Mac when Macintosh is not mounted.
  5. Restore access to the damaged Mac by externally booting from the target startup disk on the host Mac.

When you need file transferring or data recovery from one Mac to another, taking advantage of Mac Target disk mode helps a lot. But when the situation is out of its control, a reliable software like iBoysoft Data Recovery for Mac would help you out as well.