Booting from a USB Key

Warning: Backup your important data before using USB as it will overwrite anything on the USB key.

Download a USB disk:

Creating USB Key on Linux

Insert a USB key in your compute and find the device name. Then use following command:

cat ipxe.usb > /dev/sdX


dd if=ipxe.usb of=/dev/sdX

where sdX is your usb drive.

The USB key should be ready to eject once finished.

Creating USB Key on MacOS


diskutil list

to get the current list of devices

Insert the flash media.


diskutil list

again and determine the device node assigned to your flash media (e.g. /dev/disk2).


diskutil unmountDisk /dev/diskN

(replace N with the disk number from the last command; in the previous example, N would be 2).


sudo dd of=/dev/rdiskN bs=1m
  • Using /dev/rdisk instead of /dev/disk may be faster
  • If you see the error dd: Invalid number '1m', you are using GNU dd. Use the same command but replace bs=1m with bs=1M
  • If you see the error dd: /dev/diskN: Resource busy, make sure the disk is not in use. Start the 'Disk' and unmount (don't eject) the drive


diskutil eject /dev/diskN

and remove your flash media when the command completes.

Creating USB Key on Windows

Check out Universal USB Installer to install the ISO file to a USB key.


Once you've created your key, reboot and set your BIOS to load the USB key first if it's not set for that already. You should see iPXE load up either load up automatically or prompt you to set your networking information up.