LinuxCon + CloudOpen + ELC-E Europe 2014

Managing QEMU overlay-based virtual machine snapshots can become cumbersome over a period of time. With each new snapshot, a new QCOW2 overlay file is created -- this can become an overhead of tracking multiple disk image files. Understanding the ability to manage multiple disk image chains efficiently will help lower this overhead.

This talk aims to explore some of the recent improvements in QEMU and libvirt projects that address this need of advanced disk image management. More specifically, we'll discuss -- shortening disk image chains, snapshot merging, live backup of entire disk image chain, gracefully reverting and deleting snapshots. We'll also see how some of these underlying concepts are used in higher-layer projects like OpenStack to create and manage snapshots. This session also includes a demonstration of some the snapshot management techniques discussed.