Proposal: Disk import/export

Proposal to improve disk import/export

There are various ways to move a disk into or out of a system via the XenAPI, both "official" (ie. via an API) and "unofficial" (ie. by working around missing APIs). Many of the "official" ways to move disks around use non-standard and poorly-documented protocols and formats, which inhibits interoperability with other services such as CloudStack and OpenStack. The "unofficial" ways are often risky since they potentially conflict with running operations (e.g. vhd coalesce).

This document starts with an overview of what we currently have; followed by an analysis of use-cases we'd like to support (or improve our support for); followed by a set of principles to govern our designs; and finally by a proposed set of APIs and CLI commands.