
Target Disk Mode over USB only works when connected via USB 3, so it can only be.

The 2016 MacBook Pro also offers Target Disk Mode over USB, in addition to Thunderbolt and FireWire (though the latter requires two adapters). But not all adapters are known to work correctly in Target Disk Mode, so if you can, connect directly to the same port type. The MacBook 12 does not offer Thunderbolt (and, by extension, FireWire), but Target Disk Mode is available over USB. If the Mac is not booting into TDM, please contact Apple for support for Target Disk Mode. MacBook, MacBook Pro), it is highly recommended that the power supply be connected to provide continuous power to the device. Proceed to Section IV What to Expect on the Falcon. Using adapters to connect Thunderbolt to FireWire will usually work, as will Thunderbolt to USB-C. The Mac should now be in Target Disk Mode. Ideally, you should connect similar ports that is FireWire to FireWire, Thunderbolt to Thunderbolt, or USB-C to USB-C.

We recommend shutting down both Macs before proceeding, however. All of the connection types (FireWire, Thunderbolt, and USB-C) support hot connecting, meaning you can connect a cable between the two Macs while they are powered on. That may seem obvious, but it makes sense to point out that Target Disk Mode only works between two Macs you can’t chain multiple Macs together. I can't find a specific Apple KB reference, but the consensus seems to be that you need Firewire, Thunderbolt or USB-C USB 2 doesn't appear to be supported.įrom the MacSales blog - Mac OS 101: How to Boot and Use a Mac in Target Disk Mode
