Making Virtual Machines with KVM and Virt-manager

I have used virtual machines for a quite a while now and have drifted back and forth between VMware and Virtualbox. While my initial experience of Virtualbox was good, between the acquisition by Oracle, the TAINT_CRAP thing and generally finding it slow and sometimes overly complicated, I thought I would explore some other options. Having recently discovered my laptop supports hardware virtualization, I thought I would try out KVM.

KVM stands for Kernel-based Virtual Machine and Ubuntu’s documentation sums up the expected uses nicely; “Ubuntu uses KVM as the back-end virtualization technology primarily for non-graphic servers”. So while this is definitely created with servers in mind, I figure I will explore using it as a Virtualbox replacement and see how that goes.

So after enabling virtualization in my BIOS I installed all the packages:

sudo apt-get install virt-manager qemu-kvm libvirt-bin ubuntu-vm-builder bridge-utils

The first thing I learned after starting virt-manager is that KVM is using QEMU as its processor emulator. This becomes obvious when you launch virt-manager and notice that it can’t connect to QEMU on localhost.
To get that working just add yourself to the libvirtd group. I did it manual style:

sudo vim /etc/group

and add yourself to the group like so:


After that you will need to logout and log back in (restarting works too) and you should see localhost(QEMU) in the virt-manager GUI indicating that a connection has been made.

The process of setting up a virtual machine is similar to what you would find in VMWare or Virtualbox. Just click the “Create new virtual machine” button and its pretty self explanatory. One thing that stood out as a little concerning is an little red error icon when setting up the network config.

If you mouse over it, it says “could not initialize HAL for interface listing”. HAL of course has been deprecated and removed from Ubuntu (and replaced by Udev) so its not a surprise that it can’t be found. I wasn’t sure what to make of this but it turns out not to be an issue; the VM boots up happily and is able to sort out a network connection just fine.

HAL error in virt-manager
I am curious to see what it will be like to work with this for a while. Particularly doing things like using the VM as a server of various kinds which is terribly clunky in with Virtualbox. Well I still have lots of tinkering to do but this is enough to get the experiment underway.