If the above method doesn’t work, you can force unmount the drive. The Terminal command to unmount an external drive is shown next: diskutil unmount $DriveID To install macOS on an external USB drive or an external hard drive you need to have a minimum 16 GB free space. To remount the drive, you require to unplug the drive and plug it again.īut you can easily unmount and remount your external hard drive using the Terminal command without the need to reconnect the storage device. If you install macOS on an external USB drive, it will eventually have all the features of a recovery partition as well as a live operating system to boot your Mac from. In GUI, you need to plug the external hard drive into your Mac to mount it automatically while drag and drop the drive icon to Trash to eject or unmount it. Insert your NTFS drive or USB stick and click to highlight the disk name in the white box on the left-hand side of the window. Unmount or Mount External Drive Using Terminal The correct DriveID is required to manage your external hard drive using Terminal. Please note down the external hard drive's identification a sample DriveID could be /dev/disk2. Alternatively, you can look for the external hard drive using the following command: ls /Volumes This command will return all the mounted or unmounted drives and their partitions. The command line to view the list of all your connected drives is as follows. The first thing you would like to do with your external drive is to view it using Terminal.

The next sections describe commonly used Terminal commands and free Mac data recovery software to salvage your lost data. In that case, you can still recover your data using data recovery software. And suppose you didn’t back up your data and executed some unsafe commands that resulted in a data loss disaster. The backup ensures you can restore data in case of any data loss event. So, back up your Mac before using Terminal to avoid data loss due to the remove command's accidental use.

But, Terminal won’t show any warning while executing any commands. The app will execute the requested command immediately.

All you need to do is enter the required Terminal command, then hit Return. Terminal helps you manage your external hard drive far better than the GUI.

How to partition external drive on imac