Document use of dd to write isohybrid+UEFI ISO images to USB drive

en/quickstart/usb_quickstart.rst

@@ -21,8 +21,24 @@ Requirements
  * For a 4 GB USB flash drive, use osgeo-live-mini ISO (without Windows and Mac installers), without persistence.
  * For a 8+ GB USB flash drive, use either osgeo-live-mini ISO, or osgeo-live ISO (with Windows and Mac installers). 8+ GB is recommended if you wish to support persistence.
 
+Creating bootable USB drive with ``dd`` under Linux
+--------------------------------------------------------------------------------
 
-Creating bootable USB drive from Ubuntu
+ISO images for OSGeo-Live 10.5 and later are *isohybrid* (and for amd64, also support UEFI boot). Under Linux, these images can be written directly to the block device for a USB drive with the ``dd`` command-line utility:
+
+.. code-block:: console
+
+   sudo dd if=osgeo-live-10.5-amd64.iso of=/dev/sdX bs=4M; sync
+
+* ``/dev/sdX`` is the block device for the USB drive, where ``X`` might be ``b`` or ``c``.
+* Use ``lsblk`` to list block devices and ``dmesg`` to see kernel messages identifying the USB drive when it is connected.
+* The USB drive should not be mounted.
+* ``sudo`` is not required if the command is run as ``root``.
+
+.. warning::
+   Be certain to select the correct block device as ``dd`` will overwrite it without question, even if it is your primary system drive.
+
+Creating bootable USB drive with Ubuntu Startup Disk Creator
 --------------------------------------------------------------------------------
 
 (This is the recommended process for creating a USB. It is applicable to Ubuntu and Ubuntu variants such as OSGeo-Live.)

osgeolive.css

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