Boot from USB pen drive

The biggest hurdle I had installing [Debian]( on my new server was getting the Debian Net Install ISO onto a USB stick in a way that would be bootable.

My new server hardware doesn’t have an optical drive, nor does it need it. It does, however, happily boot from USB.

I tried using Disk Utility under OS X to write the ISO to the memory stick, but for some reason I couldn’t mount the ISO, OS X said that it didn’t contain a valid file system – which was rubbish because I did get the ISO onto the memory stick and installing Debian with it was a piece of cake.

I also tried using the


command, all that did was copy the disk image to the device, but it was not bootable, and was not what I wanted.

I found various suggestions around the web, but I couldn’t make them work. I eventually found [UNetbootin](, a project hosted by [SourceForge]( UNetbootin will extract the contents of an ISO and write them to a USB stick in exactly the same way that they would be written to a CD (which was the original intention with ISOs).

To make the USB bootable UNetbootin also adds some other code to the device, this through me when I booted from my USB memory stick. I expected to see a regular Debian boot screen but was instead shown something else, though it contained a menu that had all the regular Debian options. I chose install and it all went smoothly – which is how I’ve always found a Debian install.

So that’s a big thumbs up for UNetbootin, it’s available for OS X, Linux, and Windows, and it’s free. A big thank you to the authors.