title: How to make an initrd.img in Ubuntu?
body: <p>[Environment: Ubuntu 10.04]</p>
  
  <p>I've just finished compiling Linux-2.6.20 and wanna make it work, so I think I should add something to my grub2, as I finished </p>
  
  <pre><code>make modules_install
  make install
  </code></pre>
  
  <p>in /boot/,I got </p>
  
  <pre><code>vmlinuz-2.6.20
  System.map-2.6.20
  config-2.6.20
  </code></pre>
  
  <p>So I just tried</p>
  
  <pre><code>mkinitramfs -o initrd.img-2.6.20 2.6.20
  </code></pre>
  
  <p>Then the file initrd.img-2.6.20 was generated, but after I type </p>
  
  <pre><code>update-grub2
  </code></pre>
  
  <p>That image file is not found! Does anyone know how to deal with this?</p>
  
  <p>By the way,I really wonder from which files is initrd.img-2.6.20 generated? Because it seemed that I didn't even specify any source to generate this file.</p>