Setting up Ubuntu 8.04 Server on VirtualBox

Yesterday, I was trying to install Ubuntu 8.04 server on my desktop using VirtualBox to set up a virtual LAMP server to play with.

VirtualBox is a virtualizer software like VM-Ware or Virtual PC. It is supported by Sun and is the the only one which is open source. It’s a pretty slick piece of software and  comes with a set of pre built host environments on which you can install various operating systems.  It has a nice intuitive user interface and pretty full featured.

So, I started off on my installation – picked Ubuntu host environment and assigned 512 MB of RAM and 10GB for the hard drive. Then I pointed it to the Ubuntu 8.04 server install ISO and off I went through the install. The install itself went off without any problems – I chose the LAMP server setup and everything went smoothly. The problem was after the install when I tried to boot up the server – I got the following error –

The kernel requires the following features not present on the CPU


Unable to boot - please use a kernel appropriate for your CPU

So I Googled around for the error and got some blog posts (oh good so I am not crazy :-)) that I went through and I thought I’d summarize it here for reference. So here goes –
The Ubuntu 8.04 Server installation comes with a kernel that assumes that Physical Address Extension (PAE) is enabled in the processor. This is a feature in x86 and x86-64 bit processors that allow them to address more that 4GB of physical address space (which makes sense – this is a server install after all…). This feature is not turned on by default in the VirtualBox software’s virtual processor.  The simple solution is to enable this feature in the VirtualBox software – one does that as follows –

  1. Shutdown the Virtual Machine (VM) instance.
  2. Open the settings on the VM through the VM VirtualBox manager
  3. Go to  -> General -> Advanced -> check Enable PAE/NX
  4. Start your VM
  5. Check to ensure that the Virtual Machine boots properly

That’s it – many thanks to the following bloggers and their blog entries :-)

  1. Hype-Free
  2. Blog Foo