## KVM Provider

To interact with the [KVM](http://www.linux-kvm.org/) (Kernel-based Virtual Machine) provider, Veewee uses [libvirt support](http://libvirt.org/ruby/) provided through the [Fog gem](http://fog.io).

To interact with the screen, Veewee enables VNC on the created KVM machines
and uses the [Ruby-VNC gem](http://code.google.com/p/ruby-vnc/) to send the keystrokes. Sending keystrokes too fast is a problem for this setup as well.

**NOTE:** VirtualBox doesn't like KVM to be enabled.

## Prerequisites

Depending on your operating system you may need to install packages for kvm,
qemu and libvirt.

If you have problems compiling the libvirt gem, check if you have the 'dev' parts installed too. 
f.i ``apt-get install libvirt libvirt-dev``

To check if your kernel can run kvm:

    # kvm_ok or kvm-ok command (on Ubuntu at least)
    $ kvm_ok
    
    # or look for vmx or svm in /proc/cpuinfo
    $ grep '^flags' /proc/cpuinfo | grep -E --color '(vmx|svm)' 

The kernel modules needed are the following: `kvm`, `kvm_intel` or `kvm-amd`.

### Storage Pool

You need to have at least one storage pool defined in libvirt where your VM
images will be stored. You can check all available storage pools with:

    $ virsh pool-list

If no storage pool is listed, you can create a new storage pool which saves all
VM images in the directory /var/lib/libvirt/images with:

    $ mkdir -p /var/lib/libvirt/images
    $ cat > /tmp/pool.xml << EOF
    <pool type="dir">
      <name>virtimages</name>
      <target>
        <path>/var/lib/libvirt/images</path>
        <format type='qcow2'/>
      </target>
    </pool>
    EOF
    $ virsh pool-create /tmp/pool.xml

### Network

You need to have at least one network defined. You can check all available
networks with:

    $ virsh net-list

If there is no network, consult the documentation of your operating
system to find out how to create it. More information can also be found in the
[libvirt documentation](http://libvirt.org/formatdomain.html#elementsNICS).

If you are using libvirt with a URI different than the default `qemu:///system`,
you need to create a config file for fog.io. If your libvirt endpoint is
accessible at `qemu+ssh://cloud@myhost.com/system` you can create the .fog config
file with:

    $ cat > ~/.fog << EOF
    :default:
      :libvirt_uri: qemu+ssh://cloud@myhost.com/system
    EOF

For more information have a look at the
[libvirt documentation](http://libvirt.org/drvqemu.html#uris).

## Using `veewee kvm` Subcommand

You can always get help by using the the built-in help with every command:

    $ bundle exec veewee kvm help build

List available templates:

    $ bundle exec veewee kvm templates

Use one of the listed templates to define a new box e.g. with:

    $ bundle exec veewee kvm define 'My Ubuntu 12.10 box' 'ubuntu-12.10-server-amd64'

Build the box using KVM / Quemu (this will take a while) with:

    $ bundle exec veewee kvm build 'My Ubuntu 12.10 box'

You can specify the name of the storage pool and the network to be used when
building a VM. Use the options`--pool-name` and `--network-name` with the built
command:

    $ bundle exec veewee kvm build 'My Ubuntu 12.10 box' --pool-name virtimages --network-name default