KVM

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KVM is a virtualization engine, like VirtualBox or VMWare. It is not locked to a Gui; this makes it more suitable for use on servers. Along the same line, it automatically sets up a virtual console using SPICE(http://www.spice-space.org/) or VNC. This allows out of band access to a virtual machine, sort of like IPMI.

KVM and QEMU are the back end components. The "hypervisor". libvirt is a wrapper making the VMs easier to manage. virt-manager is a GUI for libvirt

I am testing it on Dart, a server that runs Debian 7.

Primary goals

I want to migrate wildsong.biz and hupi.org to virtual machines so that I can host them on Dart but still keep them walled off in their own worlds to make them easier to manage.

Also I need to be able to run Ubuntu to test out BigBlueButton. (It seemed the easiest path at the moment.)

Set up

Preparing host machine

Package installation

sudo apt-get install qemu-kvm virtinst virt-top libvirt0 libvirt-bin virt-manager

Network

To make networking work the way I expect I had to put the host into bridge mode, by changing /etc/network/interfaces so that it looks (more or less) like this

# Replace old eth0 config with br0
auto eth0 br0

# Use old eth0 config for br0, plus bridge stuff
iface br0 inet dhcp
   bridge_ports    eth0
   bridge_stp      off
   bridge_maxwait  0
   bridge_fd       0

= Create a new guest machne

Initially I followed instructions to create a machine using only kvm but then found out about libvirt. I started over again at this point.

I also found it messy to work with libvirt and kvm as a regular user so I gave up on that too, I only want to start up machines and let them run.

sudo -i
mkdir /var/kvm
cd /var/kvm
virt-install --name hupi --ram=1024 --disk path=hupi.img,size=10 --network bridge=br0 \
 --graphics vnc,password=supersecret \
 --cdrom=debian-7.8.0-amd64-netinst.iso --os-type=linux --os-variant=debianwheezy \
 --description=HuPI.ORG

When working remotely, if you log in to your host machine with "ssh -Y host" then virt-viewer will now open magically. No need to forward ports or install a VNC client etc.

Using virt-install and specifying skirted around problems I was having with networking too. It worked on the first try. YAYAYAYAYA!!!

Notes continue for HuPI on the dedicated page: hub

Securing access

Seems quite open at the moment. I need my password in the guest, that's all. If I don't need VNC from the big Internet I can disable the port forwarding in my firewall.

Remote access

SPICE

VNC - I am using because it's built in. Once the machine is running properly I have no immediate need for a GUI console.