Into the libvirt

You might gather by now that QEMU incantations can get quite unwieldy once you start avoiding defaults – so it’s common for people to store these in a script, or use some kind of frontend for QEMU. The modern way to wrangle this is with Red Hat’s Libvirt. This isn’t a frontend – we’ll meet Virtual Machine Manager soon, which is – but rather an API that provides access to virtualisation functions through its daemon, libvirtd. Libvirt supports a number of hypervisors, including KVM and VirtualBox.

This might seem, to the layman, like adding another layer of complication on top of something that’s complicated enough. That’s a reasonable point; if you just want to set up a VM to try the occasional Linux distro, it’s easy to or any other friendly frontend. Where Libvirt comes into its own is with management. It can take care of storage (resize virtual disks or create pools), networking (no messing around with handcrafting network bridges) and, naturally, can create, start and stop VMs. To some extent it also abstracts the user out of the business of running the VMs, and this is generally good.