Preparing Files for USB Memory Stick Booting There are two installation methods possible when booting from USB stick. The first is to install completely from the network. The second is to also copy a CD image onto the USB stick and use that as a source for packages, possibly in combination with a mirror. This second method is the more common. For the first installation method you'll need to download an installer image from the netboot directory (at the location mentioned in ) and use the flexible way explained below to copy the files to the USB stick. Installation images for the second installation method can be found in the hd-media directory and either the easy way or the flexible way can be used to copy the image to the USB stick. For this installation method you will also need to download a CD image. The installation image and the CD image must be based on the same release of &d-i;. If they do not match you are likely to get errors The error message that is most likely to be displayed is that no kernel modules can be found. This means that the version of the kernel module udebs included on the CD image is different from the version of the running kernel. during the installation. To prepare the USB stick, you will need a system where GNU/Linux is already running and where USB is supported. With current GNU/Linux systems the USB stick should be automatically recognized when you insert it. If it is not you should check that the usb-storage kernel module is loaded. When the USB stick is inserted, it will be mapped to a device named /dev/sdX, where the X is a letter in the range a-z. You should be able to see to which device the USB stick was mapped by running the command dmesg after inserting it. To write to your stick, you may have to turn off its write protection switch. The procedures described in this section will destroy anything already on the device! Make very sure that you use the correct device name for your USB stick. If you use the wrong device the result could be that all information on for example a hard disk could be lost. Note that the USB stick should be at least 256 MB in size (smaller setups are possible if you follow ). Copying the files — the easy way There is an all-in-one file hd-media/boot.img.gz which contains all the installer files (including the kernel) as well as syslinux and its configuration file. as well as yaboot and its configuration file. Note that, although convenient, this method does have one major disadvantage: the logical size of the device will be limited to 256 MB, even if the capacity of the USB stick is larger. You will need to repartition the USB stick and create new file systems to get its full capacity back if you ever want to use it for some different purpose. A second disadvantage is that you cannot copy a full CD image onto the USB stick, but only the smaller businesscard or netinst CD images. To use this image you only have to extract it directly to your USB stick: # zcat boot.img.gz > /dev/sdX Create a partition of type "Apple_Bootstrap" on your USB stick using mac-fdisk's C command and extract the image directly to that: # zcat boot.img.gz > /dev/sdX2 After that, mount the USB memory stick (mount /dev/sdX /mnt), (mount /dev/sdX2 /mnt), which will now have a FAT filesystem an HFS filesystem on it, and copy a Debian netinst or businesscard ISO image to it. Unmount the stick (umount /mnt) and you are done. Copying the files — the flexible way If you like more flexibility or just want to know what's going on, you should use the following method to put the files on your stick. One advantage of using this method is that — if the capacity of your USB stick is large enough — you have the option of copying a full CD ISO image to it. &usb-setup-x86.xml; &usb-setup-powerpc.xml; Booting the USB stick If your system refuses to boot from the memory stick, the stick may contain an invalid master boot record (MBR). To fix this, use the install-mbr command from the package mbr: # install-mbr /dev/sdX