Written byAmanda Wong
How to Boot Mac in Target Disk Mode on Intel and M1 Mac
Summary: This is a guide on using Target Disk Mode, covering what it is, how to enter Target Disk Mode on Intel & M1 Mac, and how to fix Target Disk Mode not working.
Mac provides some tools to help boost up productivity and troubleshoot problems, such as repairing hard drives in Disk Utility and restoring Mac from Time Machine. Target Disk Mode is another practical program that we are going to dig deep into. Stay tuned to know more.
Table of Contents:
- 1. Target Disk Mode Overview
- 2. What you need to prepare
- 3. How to boot Mac in Target Disk Mode
- 4. How to fix Target Disk Mode not working
- 5. FAQ about Target Disk Mode
Target Disk Mode Overview
Target Disk Mode is a boot mode on Intel-based Macs that helps data transfer when Migration Assistant doesn't work. It does not boot Mac's operating system but makes Mac's drive behaves as an external storage device on the destination Mac, where you can mount, access, format, partition the drive of the Mac booted into Target Disk.
It should be noted that there is no Target Disk Mode on Apple silicon Mac. The previous Target Disk Mode is replaced by Share Disk (also called Mac Sharing Mode), a new startup option on M1 Mac. Similarly, it offers a way for you to access the startup disk of your Mac from another connected Mac.
So what you can do after entering Target Disk Mode on Mac? Now that this feature can mount your Mac's drive as an external drive on another Mac, you can view, edit, move, copy files stored on the drive just like any other external drive. But far more than that, Target Disk Mode can also be used to:
Transfer loads of files from one Mac to another.
Migrate your data from an old Mac to a new Mac.
Run Mac First Aid to repair the disk of the unbootable Mac.
Boot one Mac from another Mac.
Get files off when MacBook won't turn on.
What you need to prepare
Before proceeding to enter target disk mode on your Mac, you need to have preparations for a smooth and successful data transfer.
- Two Mac computers. The host Mac should run in macOS High Sierra or later if the drive of the source Mac is formatted as APFS.
- A compatible cable. A Firewire or Thunderbolt cable for Intel Macs. A USB, USB-C, Thunderbolt 3, or Thunderbolt 4 (MacBook Pro 2021) for Apple silicon Macs. It's best to use the same port on both Macs if possible. If not, an adapter also works.
- A Power charger. AC power source is necessary for MacBooks, in case the Mac runs out of power when using Target disk mode.
Note: If either of the two computers has macOS 11 Big Sur or macOS 12 Monterey installed, you must connect the two computers using a Thunderbolt cable.
How to boot Mac in Target Disk Mode
In the first place, you need to identify the model of your Mac, whether it is equipped with an Intel chip or an Apple silicon processor. Then you can follow the corresponding steps to boot an Intel Mac in Target Disk Mode or boot an Apple silicon Mac into Mac Sharing Mode-M1 Target Disk Mode.
How to boot an Intel Mac in Target Disk Mode
1. Connect two Macs both through the Firewire or Thunderbolt cable mentioned above.
2. If your Mac is turning on, click the Apple logo and go to System Preferences > Startup Disk, and click Target Disk Mode from the startup disk preference pane, it will restart your Mac and enter 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. For Macs with T2 or FileVault enabled, enter the password when asked.
3. Then you'll see a Thunderbolt or FireWire icon on the screen, which means that the Mac is in Target disk mode.
4. Wait until the destination Mac detects your target Mac and recognizes its startup disk as an external hard drive.
5. Then you can go ahead to copy or transfer files from the target Mac to the connected Mac easily.
How to boot an M1 Mac in Mac Sharing Mode (M1 Target Disk Mode)
There is a video tutorial to follow.
- Connect the M1 Mac with the second Mac with a USB, USB-C, or Thunderbolt cable.
- Shut down your M1 Mac, then press and hold the power button until you see the "Loading startup options" on your screen.
- Click Options, then click Continue with the requested password for your administrator account.
- From the top menu, select Utilities > Share Disk, and click the disk or volume that you want to share, then click on the Start Sharing option.
- On the second Mac, click Finder > Locations > Network.
- In the Network window of the second Mac, double-click your M1 Mac that is sharing disk or volume, click Connect As, select Guest in the Connect As window, then click Connect.
After entering Target Disk mode on Intel Mac or Mac Sharing Mode (M1 Target Disk Mode) on M1 Mac, you can transfer all the files stored on the target disk including folders, movies, music, documents, etc. For other info such as apps, user accounts, and macOS, you need the help of Migration Assistant.
How to fix Target Disk Mode not working
Sometimes, you can't boot your Mac in Target Disk Mode, or the target Mac doesn't appear as an external hard drive on the connected Mac. Don't worry. There are some remedies to fix the Target Disk Mode and M1 sharing mode not working issue.
Solution 1. Check the cables and ports
With the wrong ports or bad cables, the two Macs can not be connected successfully. Change different ports or cables to check if there is a connection problem.
Solution 2. Disable the Firmware password
With the Mac firmware password turned on, you will not be able to enter the target drive mode from a cold boot. You can boot your Mac into recovery mode, and choose Utility > Firmware Password Utility to disable it with your password.
Solution 3. Update macOS
If the hard drive on the target Mac is in APFS format, then the destination Mac must run in macOS High Sierra or later. Earlier macOS can't read APFS so it won't recognize and mount your Mac's drive.
Solution 4. Check the Preferences in Finder
When the external hard drive not showing up on Mac, it might be the Finder where you set to hide the drive. In this case, the target disk will not show up. You can check by navigating to Finder > Preferences > Sidebar > Locations. Check if the boxed next to Hard disks and External disk are ticked.
Solution 5. Mount the hard drive
If the target disk fails to appear after making changes in Finder Preferences, you can try to mount the disk manually when the external hard drive not mounting on Mac. Open Disk Utility on the connected Mac and find the target disk. If it is grayed out, select it and click the Mount button.
Unfortunately, the approaches mentioned above can not make the Target Disk Mode work on your Mac, the reason may be related to Mac's hardware malfunction. You can contact Apple Support for further help.
FAQ about Target Disk Mode
On the destination Mac, click the mounted drive of the target Mac and select Eject, or drag it to the Mac Trash, and press down the power button to turn off the target Mac, then disconnect the cable and boot your Mac as normal.
In addition to using Target Disk Mode/Share Disk, multiple ways are available to realize files transferring between two Macs such as Migration Assistant, Airdrop, File Sharing, Dropbox email, cloud service, etc. You can choose to use different ways to share files based on the number and size of the files.