Backing Up Virtual Disks in vSphere
This chapter documents how to write backup and restore software for virtual machines running in vSphere, and contains the following sections about the vSphere Storage APIs – Data Protection (VADP):
For an overview of backup, and help designing your top-level program structure, read the first section below. For details about implementing low-level backup code, read the remaining sections. You should be familiar with virtual machines, snapshots, ESXi, vCenter, and Java.