Building Debian Installer images with a custom kernel. So you want to build a custom version of the Debian Installer? This document assumes basic familiarity with bilding Debian packages from source. The techniques described here are aimed mostly at replacing the kernel, which is the most common piece to need to replace, but similar techniques can be used to replace any other udeb used by this modular installer with a custom version. If you have questions about this document, mail the Debian Installer team at: . Step 1. Kernel deb You need to find or produce a kernel deb for the kernel you want to use with d-i. This can be built in the standard Debian way with make-kpkg. The kernel should be built with the following things built in: devfs (does not need to automount on boot) tmpfs unix domain sockets support ext2 Most everything else can be modular, and it's a good idea to enable pretty much everything. A good starting place is the kernel config from an existing official Debian kernel. Once you have the kernel-image.deb, install it for the next step. On i386, you should also install the kernel-pcmcia-modules file. You do not need to boot into the new kernel. Step 2. Kernel udebs Unpack the source package linux-kernel-di-i386 (other arches, replace i386 with your arch). In its source tree, edit the kernel-versions file. Each line in this file is a kernel version, you can comment out all but one, and modify that one to match the version of your custom kernel. Make sure the build dependencies of linux-kernel-di-i386 are satisfied (you will need to install the kernel-wedge package), and build the package. This will produce several udebs. Step 3. Initrds and images Unpack the debian-installer source package. Make sure the many build dependencies are satisfied. Check that build/config/i386.cfg has a KERNELVERSION field that matches the version of your custom kernel (other arches, replace i386 with your arch). Copy the udebs that were produced in step 2 into the build/localudebs directory. Go to the build directory and type "make list" to see a list of possible targets. For example, if you want to build floppy images, use this command: fakeroot make build_floppy_boot build_floppy_root If you're looking to build a complete Debian CD, the target to use is "build_cdrom_isolinux" (and see step 4). It turns out to be much easier to build a mini CD containing just d-i, which you can do with the "build_monolithic" target. You will need a network connection to install using this image. Look in the build/dest directory for the images. The MANIFEST file will list every file you built and its purpose. Note that the build_cdrom_isolinux target does not produce an entire ISO image, but just the initrd to go on one. However, the build_monolithic target does produce a bootable ISO image, and the floppy targets do produce floppy images. Step 4. Building a full Debian CD image If you have an initrd for a CD, and some kernel udebs, and a kernel deb, you probably want to stick them all on a Debian CD. There are two ways to do this. You can install the debian-cd package and read its documentation. Be warned that using debian-cd is difficult, and requires a local Debian mirror. Or you could try to remaster an existing Debian ISO using the technique described here: http://wiki.debian.net/index.cgi?DebianInstallerModify Neither of these routes will be as relatively polished or easy as steps 1-3. We recommend that you don't try to build a full Debian CD unless you really absolutely need one, and have plenty of time to set up debian-cd. An alternative is to build a monolithic mini iso (as described in step 3).