Target Disk mode is one of the lesser-known features on the Mac. This feature is particularly useful when you want to transfer all the data to other Macbook. So this is how it works, the feature will literally turn your MacBook into an external hard drive and this will allow you to transfer data seamlessly. Before we begin please note that this feature can only be used between two Macs and doesn’t offer cross-platform compatibility.
The Target Disk feature comes in handy when you want to transfer large files quickly across Macs or in instances wherein your Mac refuses to boot and you want to access the data. Target Disk feature will mount the volumes and allow you to access data without booting your Mac. One needs to use cables in order to transfer data and this is something that will help in achieving better transfer speeds. Please note that you will not be able to use your Mac when in Target Disk Mode. However, once done you can simply reboot it and you will be good to go.
The Target Disk Mode is not exactly a new feature and has been baked into Mac for more than a decade. All you need for this is a bunch of external cables and of course two Macs to transfer the data. Let us specifically take a look at what and all is needed to use the Transfer Mode on Mac,
First things first, make sure that you have a Thunderbolt 3 Cable. You can use the older variants of Thunderbolts cable but not USB cables. Now you need to connect both the Macs with Thunderbolt cable. The device which you want to access is the Target while the device via which you intend to do so is the Host. Please ensure that your MacBook is charged and has enough power for the data transfer. I personally advise you to plug in the power source.
If your Mac is encrypted using File Vault you need to enter the password while starting the target Mac. You can proceed with the operation only once the drive is decrypted completely. Head over to Settings>Startup Disk.
Now you can access all the files from the host Mac by going to Finder. You can copy, paste and move files. Once done you need to either drag the drive icon to the trash or select Eject. The biggest advantage of this is that you can transfer/backup entire Mac without having to use an external hard disk as a bridge.
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