This page is about booting Linux via USB pendrives in any computer with or without USB-BIOS capability (in this last case, using a ?BootFloppy). You can install Linux in your USB pendrive or buy it preinstalled.
If you don't want to learn about the internals but just have Debian on a bootable USB stick, check out DebianLive
BIOS and USB standard mass storage interface
There are two common BIOS methods for direct USB booting:
- One method is called the "USBHDD" method and it is used to support the booting of standard USB mass storage devices that are configured like a normal PC hard drive. The vast majority of machines work this way these days.
- The other method (necessary on some older machines) is called the "USBZIP" method and it supports booting from a USB storage device that behaves like the original IOMEGA ZIP drive with USB support.
You need a USB device with a standard mass storage interface and with at least 128 MB storage capacity (the distros generally use between 50 and 64 MB) to work with Linux.
The following instructions refer to /dev/sda. However, if you have serial-ATA harddisks, then the pendrive will probably be /dev/sdc. Do NOT accidentally write to the wrong drive, or you will destroy your main operating system or data!
USB pendrive location and mount
Most USB pendrives are located at device node /dev/sda after they are plugged into the USB port.
However, you can verify this location by typing this command inside a terminal emulator window:
dmesg | grep scsi -A 3
and it should tell you the device name for your USB (SCSI emulated) devices, along with the vendor name.
and mount the usb filesystems
mount -t usb-devfs none /proc/bus/usb
Writing an image onto the USB key
The current released versions of Debian Install images and Debian Live images are built using isohybrid techniques, which means using them with a USB key is simple and easy, using "dd". See the Debian CD FAQ for more information.
Older Debian images were not so easy to use with USB keys and needed a lot of instructions. Those instructions are no longer helpful, so have been removed from this page.