Linux - How to Write ISO to USB
The modern way to install an OS on a physical piece of hardware is to use a USB drive. Operating systems are generally distributed as ISO files ( CD/DVD images ). These generally need to be written to a USB drive before you use them on physical hardware. You won’t need to do this for a VM. In that case you can just mount the image.
To write an ISO to USB you can use these tools ( among others ):
- The dd command from a terminal
- The Startup Disk Creator tool
WARNING - Make sure you have the correct disk. You don’t want to write over a hard disk, SD card, or the wrong USB drive. You can identify the disk from the command line using the lsblk command or from a GUI using the gnome-disk-utility which is usually just called “Disks” because they didn’t want to make it distinctive and because they wanted to confuse people ( still a great tool ).
Linux: How to Write ISO to USB from the Command Line
First, identify the USB drive that you intend to use. One way to do this is with the lsblk command which you can run like this:
You can write the ISO image to your USB disk using the dd command like this:
sudo dd bs=4M if=~/Downloads/ubuntu-20.04.1-desktop-amd64.iso of=/dev/sdb conv=fdatasync
You will need root permissions so use sudo. You will want to set the block size to 4M for efficient read/write using the “bs=4M” option. The “if” option specifies the path to the input file ( the ISO image that you want to write). The “of” options specifies the device you want to write to ( your USB drive ). Using “conv=fdatasync” should tell it to flush the write buffers before the tool shows that it is completed.
Easy GUI Method 1
If you are running Ubuntu on your desktop ( probably other distros too ) it is really to write an ISO image to a USB drive. You just launch the “Startup Disk Creator” which should normally be installed by default. To find it, just click on the application menu and start typing “Startup ….”. It will be one of the first things you see.
It is super ridiculously easy to use. Just do the following:
- Select the ISO image
- Select the USB drive
- Click “Make Startup Disk”
Easy GUI Method 2 - Linux, Windows, Mac OS
There is a tool called Etcher that is incredibly easy to use. It works for Linux, Windows, and Mac OS. You can download it here:
You can basically just select the ISO image you want, select the USB drive you want, and click “write”.
Another popular tool is UNetbootin. It has a few more options and is geared towards creating bootable live systems.
You can find this tool here: