I have a 2019 13" MBP and a 2017 MBA. I put my MBA into target disk mode and hooked it up to the MBP using an Aukey USB C to USB A cable. The MBA does not appear on my MBP. Do I need some special cable to make this work?
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MP 7,1 Target Disk Mode
- Thread starter hellfried
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Suggest that you ask in a MacBook forum - this one is for the desktop "Pro" machines.
I do see the thunderbolt icon on the screen of my MBA. I was under the impression that it would work over USB A as well.
It appears that USB TDM is not an option for non-USB-C Macs. You can do TDM over USB-C, that’s how the MacBook 12 inch did TDM, and apparently the Thunderbolt 3 Macs can operate with USB or Thunderbolt, but before TB3 they used Thunderbolt exclusively, and before that Firewire, and before that SCSI.
You can plug in Thunderbolt 2 to Thunderbolt 3, then Thunderbolt 2 cable to connect a TB2 Mac to a TB3 Mac.
You can plug in Thunderbolt 2 to Thunderbolt 3, then Thunderbolt 2 cable to connect a TB2 Mac to a TB3 Mac.
I will try the other way round when I am home this evening. Looks like I still need Airdrop to transfer files from the MBA to the MBP.
I put my MBP into target disk mode and my MBA went as far as asking me for the password to unlock the drive. The drive, however, does not show up on my desktop. I can see the drive in disk utility but it says 'not mounted' or words to that effect.
target mode works on:
TB > TB
TB > TB2
TB2 > TB2
TB2 > TB3 (with apple TB2toTB3 adapter and TB2 cable)
TB3 > TB3
FW > FW
USB-C > USB-C
edit:
USC-C > USB-A (only if it USB3.0 !)
no USB2.0
and in no other configurations!
TB > TB
TB > TB2
TB2 > TB2
TB2 > TB3 (with apple TB2toTB3 adapter and TB2 cable)
TB3 > TB3
FW > FW
USB-C > USB-C
edit:
USC-C > USB-A (only if it USB3.0 !)
no USB2.0
and in no other configurations!
Last edited by a moderator:
Doubtful. It's about the capabilities of the port, not the actual connector.
I'm not sure any USB, except for C, has ever worked for Target Disk Mode.
OK thanks for all the replies even though I posted this question in the wrong forum (apologies to the moderators).
From what I’ve read, Macs equipped with USB-C can use Thunderbolt protocol or USB protocol as the Target Disk Mode host. This means you can use the USB-C to USB-A cable (if the cable has Superspeed USB 3.0 or 3.1, also the receiving Mac may need to support USB 3.0 or later too, which the 17 MBA of course supports 3.0 so it’s good there). So any Mac with a Thunderbolt 3 port supports both protocols, and the MacBook 12 inch supports USB only as its port is USB only and not Thunderbolt. But, for Macs without Thunderbolt 3, as a host they need Thunderbolt on both sides and the right cables. So if you want to go from the 17 MBA to any other Mac, you have to use a TB2 to TB2 cable to either a TB2 Mac, or if it’s TB3 it needs the Apple TB2 to TB3 adapter. You also cannot use a TB3 cable, the adapter only takes a TB2 cable on the female end and it’s a TB3/USB-C plug. Also it has to be a Thunderbolt cable, not miniDisplayport (there’s a difference, the Thunderbolt logo is on Thunderbolt cables, it’s a lightning bolt). And remember, if you use Thunderbolt protocol correctly it actually can go in both directions so you could have either running as Target Disk Mode. If you had two Thunderbolt 3 Macs then you could use a Thunderbolt 3 cable and connect the two as well with no adapter and run in both directions too.
This specification came with the Aukey cable I bought.
- DateSync and Charging: the data transmission speed of USB 3.1 to USB C can be up to 5 Gbps, it is 10 times faster than USB 2.0, and also is fast and stable for data transmission.
MBP with Thunderbolt 3 can be a host and work with such cable to the Air with USB 3.0. The other direction, as I said, does not work as it needs to be Thunderbolt and therefore TB2 to TB2 cable to TB3 to TB2 adapter.
I tried out USB-C to USB-A with a Thunderbolt 3 Mac as TDM host (MBP 15) to a retina Macbook Pro with USB-A (3.0) and it works fine! The receiving Mac needed me to put in my password of course since it's using Filevault.
My retina MBP however cannot be a TDM host as it does not support USB TDM but my TB3 Mac does. So of course as I say you could go in the direction of the TB3 Mac to the MBA but not the other way unless you invest in a Thunderbolt 2 cable and adapter to go from Thunderbolt 2 to Thunderbolt 3.
Protip: When TDM is activated the screen of the Mac shows which protocols it supports by logo. My TB3 equipped Macbook Pro shows USB and Thunderbolt logos. My retina Macbook Pro shows only a Thunderbolt logo. I have seen that older Macs with Firewire would show the Firewire logo. Some Macs don't support TDM at all because they didn't have Firewire and it was pre-Thunderbolt entirely and I guess they didn't want to run it over USB (you'd need a special crossover cable to run USB-A to USB-A if that was supported, but it wasn't supported).
Also just in general the OS on the receiving end needs to understand the filesystem of the TDM host in order to mount, obviously if you use a MacOS that doesn't have APFS for instance then it won't be able to work with an APFS system.
My retina MBP however cannot be a TDM host as it does not support USB TDM but my TB3 Mac does. So of course as I say you could go in the direction of the TB3 Mac to the MBA but not the other way unless you invest in a Thunderbolt 2 cable and adapter to go from Thunderbolt 2 to Thunderbolt 3.
Protip: When TDM is activated the screen of the Mac shows which protocols it supports by logo. My TB3 equipped Macbook Pro shows USB and Thunderbolt logos. My retina Macbook Pro shows only a Thunderbolt logo. I have seen that older Macs with Firewire would show the Firewire logo. Some Macs don't support TDM at all because they didn't have Firewire and it was pre-Thunderbolt entirely and I guess they didn't want to run it over USB (you'd need a special crossover cable to run USB-A to USB-A if that was supported, but it wasn't supported).
Also just in general the OS on the receiving end needs to understand the filesystem of the TDM host in order to mount, obviously if you use a MacOS that doesn't have APFS for instance then it won't be able to work with an APFS system.
I got as far as my host MBA asking for the password to unlock the TDM (MBP). Nothing happens after that. In Disk Utility the TDM appears grayed out and its not mounted.
Could be a bad cable. Or the MBA does not understand the filesystem of the MBP. You might have better luck with Thunderbolt as well.