How to Mount an Ubuntu Drive as an External USB Boot Drive
- 1). Shut down the computer you want to boot the external drive on. Connect the drive to the machine via the USB cable. If there is an external power adapter for the USB drive, make sure that the adapter is plugged into a working outlet.
- 2). Power on the machine and watch for the on-screen notification that displays what key to press to enter the BIOS settings. This will be different for every motherboard manufacturer, though many use the "F2" or "Delete" keys. Additionally, some manufacturers may require you to press "Esc" to cancel out of a splash screen.
- 3). Press the BIOS settings key, then use the arrow keys to navigate the BIOS to the Boot Menu. Once again, every manufacturer will have this in a different place depending on the BIOS make and version number. Use the necessary keys, often "Page Up" and "Page Down," to rearrange the boot devices so the external USB hard drive is first.
- 4). Use the arrow keys to select the "Save Changes and Exit" option in the BIOS. The machine will automatically restart. When the GRUB menu appears, use the arrow keys to select Ubuntu Linux from the list. This is the first option on default installs. Press the "Enter" key to mount your root partition and boot off the device.
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