KVM provides full virtualization under Linux

Open Source just keeps getting better and better.

Been messing around with alternatives to VMWares ESX and ESXi. Of the top contender thus far is KVM.

KVM is a true kernel-level hypervisor similar to ESXi. Unlike ESXi, you still load a typical Linux OS first – the KVM runs via a special kernel module.

At first glance, I was a bit confused: you install Qemu and KVM. “So is this Qemu or is it KVM”. It is actually both. KVM is largely comprised of two components: the kernel-level hypervisor and a handfull of shared libraries and binaries shared by Qemu.

At the core, you call the “kvm” command just as you would call the “qemu” command (they take the same arguments).

Installation on Ubuntu is easy-squeezy:

apt-get install kvm qemu

Currently, kvm supports all the neato stuff you would expect from a kick-ass virtualizer:

Full virtualization that takes advantage of VTI and AMD-V extensions
Supports snapshots and machine states
Live migration of a running guest from one server to another
Multi-processor support (up to 64 I believe)
Good memory management with Windows guests

There are some GUI tools for managing the virtual machines – one of the neatest I found was virtual-manager. Similar to VMWares VCenter. I have not used this tool much however in favor of custom scripts for management.

Looks like I will be deploying this in an initial test phase at our TeirII data center in Franklin, TN for the Army National Guards website (http://www.nationalguard.com). I will keep everyone posted on how the tests turn out!