Eucalyptus is a software platform for the implementation of private cloud computing on computer clusters.
Eucalyptus implements IaaS (Infrastructure as a Service) style private and hybrid clouds. The platform provides a single interface that lets users access computing infrastructure resources (machines, network, and storage) available in private clouds—implemented by Eucalyptus inside an organizations's existing data center—and resources available externally in public cloud services. The software is designed with a modular and extensible Web services-based architecture that enables Eucalyptus to export a variety of APIs towards users via client tools. Currently, Eucalyptus implements the industry-standard Amazon Web Services (AWS) API, which allows the interoperability of Eucalyptus with existing AWS services and tools. Eucalyptus provides its own set of command line tools called Euca2ools, which can be used internally to interact with Eucalyptus private cloud installations or externally to interact with public cloud offerings, including Amazon EC2.