What is libvirt?
Libvirt is collection of software that provides a convenient way to manage virtual machines and other virtualization functionality, such as storage and network interface management. These software pieces include an API library, a daemon (libvirtd), and a command line utility (virsh). An primary goal of libvirt is to provide a single way to manage multiple different virtualization providers/hypervisors. For example, the command ‘virsh list –all’ can be used to list the existing virtual machines for any supported hypervisor (KVM, Xen, VMWare ESX, etc.) No need to learn the hypervisor specific tools!