******************************************************************** NOTE: This is Eucalyptus 3.1 under development. Please see the INSTALL file for build instructions. ******************************************************************** EUCALYPTUS: Elastic Utility Computing Architecture for Linking Your Programs To Useful Systems EUCALYPTUS is an open source service overlay that implements elastic computing using existing resources. The goal of EUCALYPTUS is to allow sites with existing clusters and server infrastructure to co-host an elastic computing service that is interface-compatible with Amazon's EC2. Because EUCALYPTUS is designed to function as an overlay, it must be able to incorporate resources from different clusters or pools. For example, EUCALYPTUS allows its administrator to set up a "cloud" that permit users to virtualized OS instances on a number of clusters transparently. Enabling the necessary network interconnectivity in a way that is secure and portable is one novel feature of EUCALYPTUS. Another stems from its ability to provide interface compatibility with the existing Amazon EC2 service. EUCALYPTUS users can develop using their own local resources and then transition directly some or all of their functionality to EC2. Finally, a key requirement of EUCALYPTUS is that it be able to serve as a research platform for elastic computing. To this end, its design makes two significant contributions. The first concerns the use of scarce network resources in a structured way. A EUCALYPTUS allocation can function equally well in an environment in which all processors have externally routable IP addresses (e.g. Amazon's current environment) as well as one in which only a certain "front-end machine" is externally routable (as is the case with many production and research clusters today). Secondly, EUCALYPTUS leverages the extensive Linux packaging and deployment support that is currently available while requiring minimal modification to the existing installed OS base. Specifically, the target resources need only run a standard hypervisor (Xen, KVM), along with common open-source Linux utilities. All other functionality installs directly without need for kernel patching or module additions to the host OS domain.