How to compile linux kernel in Debian / Ubuntu the Easy Way

Sometimes you may need to compile  for enabling a  specific module in Linux. It is easy to compile and update the linux kernel to latest stable version  for your computer or server.  At the time of  writing  of this article the latest stable version of linux kernel is  3.12. So in this article , I show you how to compile the latest kernel in debian.

First of all you need to download and  install a set of  building tools that required to compile the linux kernel in your  desktop.

1 . In stall all the  build essentials for your  compilation process,
apt-get update

apt-get install kernel-package libncurses5-dev fakeroot wget bzip2 build-essential

2. Download the latest stable kernel form and extract  it
cd /usr/src
wget -c
tar -xJf  linux-3.12.tar.xz
cd linux-3.12
3.The easy way of configuring the kernel

Before compiling  the kernel we have to configure the option. That  means we have to enable all required modules  using the command “make menuconfig ” . This article title says , it is an easy way. So let us copy the older configuration if your current kernel into the “.config” file which is the configuration file for kernel build

root@myhome:/usr/src/linux-3.12#  cp -v /boot/config-`uname -r` ./.config
4. Adding your extra kernel modules

Now run the following command and  load this .config file form the “load” table

make menuconfig

After loading the .config file old option , you can  add or remove any additional kernel modules as  you wish

5. Now build the kernel package

you may need to use the following commands from your debian shell

# make-kpkg clean
# fakeroot make-kpkg -j4 --initrd --append-to-version=-new kernel_image kernel_headers

The option “-j4” will multi thread your compilation process  between 4 cpu cores and increase the compilation time .  Also the option –append-to-version=-new add a tag “new”  to the kernel .  The kernel compilation will take 3o to 45 minutes depend on the options you selected in the make menuconfig .

6. After Finishing the compil

You may look into the directory /usr/src for seeing two debian packages named  like  as follows,


Install these packages as follows,

dpkg -i linux-headers-3.12.0-new_3.12.0-new-10.00.Custom_amd64.deb
dpkg -i linux-image-3.12.0-new_3.12.0-new-10.00.Custom_amd64.deb
7. Updating the grub

You may now update the  grub configuration using the following command

# update-grub

If you like to change the boot options please make sure to edit it in  /etc/default/grub  and update the grub after that. In  debian and ubuntu this toll will automatically propagate the grub configuration. If you are  compiling  it in a remote server, please make sure to set automatic PANIC options and reboot options in grub for a crash recovery too. After that reboot  into new kernel.

Install JAVA in Ubuntu or debian manually

The following steps will help you to install java in ubuntu / debian  manually

Download the jdk 7 tar  file

mkdir -pv /usr/lib/jvm
cd /usr/lib/jvm
wget -c http://downloads-url-of-jdk/java/jdk-7u10-linux-x64.tar.gz
tar -xzf jdk-7u10-linux-x64.tar.gz
cd /usr/lib/jvm/jdk1.7.0_10

Now set the alternatives path

update-alternatives –install “/usr/bin/java” “java” “/usr/lib/jvm/jdk1.7.0_10/bin/java” 1
update-alternatives –install “/usr/bin/javac” “javac” “/usr/lib/jvm/jdk1.7.0_10/bin/javac” 1
update-alternatives –install “/usr/bin/javaws” “javaws” “/usr/lib/jvm/jdk1.7.0_10/bin/javaws” 1

Now edit the bashrc file and set teh following environment variables

export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_10
export CLASSPATH=.:$JAVA_HOME/lib/
export PATH=$JAVA_HOME/bin:$PATH

Now you can test the java version using the following command,

# javac -version

PS: If you have multiple alternative , please configure it using   update-alternatives –config java