What follows is an analysis of the USB based target disk mode protocol, and also a revelation that the FileVault2 key may be extractable (albeit in wrapped form) from a machine without the OS booted. Moreover, Apple’s security features such as encryption and effaceable storage complicate the implementation. Modern USB and Thunderbolt based target disk mode requires a machine that is ordinarily a USB host to become a slave. Because of the peer-to-peer nature of FireWire and the standard SCSI command set, implementing a consumer in linux for this protocol was relatively straight forward. MacOS Recovery on Macs with ‌Apple Silicon‌ includes a number of other apps that can help you repair an internal disk, reinstall macOS, restore your files from a Time Machine backup, and more.In earlier generations of Apple MacBook computers, TDM or Target Disk Mode was a boot mode that made all internal drives appear to an external FireWire capable system to be LUNs which could be consumed by another endpoint (This usually included the internal Hard Drive and CD/DVD-ROMs).

When your files are transferred, eject the disk on the other Mac.

Select Guest in the Connect As window, then click Connect.

In the Network window, double-click the Mac that has the shared disk, then click Connect As.

On the other Mac, open a Finder window and click Network in the sidebar under 'Locations.'.

Select the disk you want to share with the other Mac, then click Start Sharing.

When your Mac has entered Recovery mode, choose Utilities -> Share Disk from the menu bar.

Enter the password for an administrator account if prompted.

On the same Mac, press and hold the power button until you see a screen offering 'Loading startup options.'.

If the ‌Apple Silicon‌ Mac is powered on, shut it down ( menu -> Shut Down).

Connect the two computers using a USB-C or Thunderbolt cable.Using the method described below will allow you to easily transfer your files across from an older Mac to a new ‌Apple Silicon‌ Mac. Mac Sharing Mode turns the system into an SMB file sharing server, providing another Mac with file-level access to user data.

Sharing Mode on ‌Apple Silicon‌ Macs replaces the older Target Disk Mode found on Intel Macs, and can be used similarly to transfer data between two Macs. If you have a newer Apple Silicon Mac and an older Intel Mac lying around, you can connect the two using Sharing Mode, so that the older Mac appears as an external hard disk to your new machine.

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