Loading ...How to: Compile Linux kernel 2.6
Compiling custom kernel has its own advantages and disadvantages. However, new Linux user / admin find it difficult to compile Linux kernel. Compiling kernel needs to understand few things and then just type couple of commands. This step by step howto covers compiling Linux kernel version 2.6.xx under Debian GNU Linux. However, instructions remains the same for any other distribution except for apt-get command.
Step # 1 Get Latest Linux kernel code
Visit http://kernel.org/ and download the latest source code. File name would be linux-x.y.z.tar.bz2, where x.y.z is actual version number. For example file inux-2.6.25.tar.bz2 represents 2.6.25 kernel version. Use wget command to download kernel source code:
$ cd /tmp
$ wget http://www.kernel.org/pub/linux/kernel/v2.6/linux-x.y.z.tar.bz2
Note: Replace x.y.z with actual version number.
Step # 2 Extract tar (.tar.bz3) file
Type the following command:
# tar -xjvf linux-2.6.25.tar.bz2 -C /usr/src
# cd /usr/src
Step # 3 Configure kernel
Before you configure kernel make sure you have development tools (gcc compilers and related tools) are installed on your system. If gcc compiler and tools are not installed then use apt-get command under Debian Linux to install development tools.
# apt-get install gcc
Now you can start kernel configuration by typing any one of the command:
- $ make menuconfig - Text based color menus, radiolists & dialogs. This option also useful on remote server if you wanna compile kernel remotely.
- $ make xconfig - X windows (Qt) based configuration tool, works best under KDE desktop
- $ make gconfig - X windows (Gtk) based configuration tool, works best under Gnome Dekstop.
For example make menuconfig command launches following screen:
$ make menuconfig
You have to select different options as per your need. Each configuration option has HELP button associated with it so select help button to get help.
Step # 4 Compile kernel
Start compiling to create a compressed kernel image, enter:
$ make
Start compiling to kernel modules:
$ make modules
Install kernel modules (become a root user, use su command):
$ su -
# make modules_install
Step # 5 Install kernel
So far we have compiled kernel and installed kernel modules. It is time to install kernel itself.
# make install
It will install three files into /boot directory as well as modification to your kernel grub configuration file:
- System.map-2.6.25
- config-2.6.25
- vmlinuz-2.6.25
Step # 6: Create an initrd image
Type the following command at a shell prompt:
# cd /boot
# mkinitrd -o initrd.img-2.6.25 2.6.25
initrd images contains device driver which needed to load rest of the operating system later on. Not all computer requires initrd, but it is safe to create one.
Step # 7 Modify Grub configuration file - /boot/grub/menu.lst
Open file using vi:
# vi /boot/grub/menu.lst
title Debian GNU/Linux, kernel 2.6.25 Default root (hd0,0) kernel /boot/vmlinuz root=/dev/hdb1 ro initrd /boot/initrd.img-2.6.25 savedefault boot
Remember to setup correct root=/dev/hdXX device. Save and close the file. If you think editing and writing all lines by hand is too much for you, try out update-grub command to update the lines for each kernel in /boot/grub/menu.lst file. Just type the command:
# update-grub
Neat. Huh?
Step # 8 : Reboot computer and boot into your new kernel
Just issue reboot command:
# reboot
For more information see:
- Our Exploring Linux kernel article and Compiling Linux Kernel module only.
- Official README file has more information on kernel and software requirement to compile it. This file is kernel source directory tree.
- Documentation/ directory has interesting kernel documentation for you in kernel source tree.
Want to stay up to date with the latest Linux tips, news and announcements? Subscribe to our free e-mail newsletter or full RSS feed to get all updates.
You can Email this page to a friend.
You may also be interested in...
- Download of the day: Linux kernel 2.6.24
- Howto: build Linux kernel module against installed kernel w/o full kernel source tree
- Linux: How to compile program
- Download of the day: Linux Kernel 2.6.25
- Download of the day: Linux kernel 2.6.23
Discussion on This Article:
Leave a Reply
We encourage your comments, and suggestions. But please stay on topic, be polite, and avoid spam. Thank you very much for stopping by our site!
Tags: command tar, compile_kernel, compiling linux kernel, configuration option, configuration tool, gnu_linux, how to compile linux kernel, kernel code, kernel configuration, kernel image, kernel source code, kernel v2, kernel version, latest linux kernel, linux_kernel_version ~ Last updated on: April 17, 2008
According to the kernel documentation, the kernel should be compiled using gcc 2.95.x, with x >= 3. “apt-get install gcc” under debian gives you a recent gcc (version > 4).
It works with gcc version >= 4.0.
gcc –version
gcc (GCC) 4.0.3 20060212 (prerelease) (Debian 4.0.2-9)
uname -a
Linux debian 2.6.15.4 #1 PREEMPT Fri Feb 17 20:46:04 IST 2006 i686 GNU/Linux
I have compiled above kernel using gcc 4.0.2-9. INSTALL file may be not updated.
Thanks a lot Gabber Anna,
It’s works for me :-))
LOL
Note sure who are you?
But you bring back some old memories…
Take care buddy
any guess about boot loader?
After building the kernel and updating grub I’ve rebooted the new kernel successfully. Now I am wondering if this process includes updating the kernel header files in /usr/include/. If not, what is the best way to do that and should any new directories be added to ld.so.conf so I can update glibc?
If you also upgraded kernel-devel and headers package you should get updates. No need to upgrade ld.so.conf or cache
Info
—–
Kernel 2.6.23 has issues with kernel headers. If you have distro’s like fedora it gonna give up some wierd fixdep.c error messages.
Some forums say you need to have 2.4 headers for compiling it. Kernel header is a huge mess scattered around and well serious debates have gone down the drain…
http://kerneltrap.org/node/6536
Does this kernel support RHEL4 update 5
I am using kernel 2.6.9-55.EL can i upgade the
How much time does it take approximately?