The Ubuntu Enterprise Cloud documentation uses terminology that might be unfamiliar to some readers. This page is intended to provide a glossary of such terms and acronyms.
Cloud - A federated set of physical machines that offer computing resources through virtual machines, provisioned and recollected dynamically.
Cloud Controller (CLC) - Eucalyptus component that provides the web UI (an https server on port 8443), and implements the Amazon EC2 API. There should be only one Cloud Controller in an installation of UEC. This service is provided by the Ubuntu eucalyptus-cloud package.
Cluster - A collection of nodes, associated with a Cluster Controller. There can be more than one Cluster in an installation of UEC. Clusters are sometimes physically separate sets of nodes. (e.g. floor1, floor2, floor2).
Cluster Controller (CC) - Eucalyptus component that manages collections of node resources. This service is provided by the Ubuntu eucalyptus-cc package.
EBS - Elastic Block Storage. http://aws.amazon.com/ebs/
EC2 - Elastic Compute Cloud. Amazon's pay-by-the-hour, pay-by-the-gigabyte public cloud computing offering.
EKI - Eucalyptus Kernel Image.
EMI - Eucalyptus Machine Image.
ERI - Eucalyptus Ramdisk Image.
Eucalyptus - Elastic Utility Computing Architecture for Linking Your Programs To Useful Systems. An open source project originally from the University of California at Santa Barbara, now supported by Eucalyptus Systems, a Canonical Partner.
Front-end - Physical machine hosting one (or more) of the high level Eucalyptus components (cloud, walrus, storage controller, cluster controller).
Node - A node is a physical machine that's capable of running virtual machines, running a node controller. Within Ubuntu, this generally means that the CPU has VT extensions, and can run the KVM hypervisor.
Node Controller (NC) - Eucalyptus component that runs on nodes which host the virtual machines that comprise the cloud. This service is provided by the Ubuntu package eucalyptus-nc.
S3 - Simple Storage Service. Amazon's pay-by-the-gigabyte persistent storage solution for EC2. http://aws.amazon.com/s3/
Storage Controller (SC) - Eucalyptus component that manages dynamic block storage services (EBS). Each 'cluster' in a Eucalyptus installation can have its own Storage Controller. This component is provided by the 'eucalyptus-sc' package.
UEC - Ubuntu Enterprise Cloud. Ubuntu's cloud computing solution, based on Eucalyptus.
VM - Virtual Machine.
VT - Virtualization Technology. An optional feature of some modern CPUs, allowing for accelerated virtual machine hosting.
Walrus - Eucalyptus component that implements the Amazon S3 API, used for storing VM images and user storage using S3 bucket put/get abstractions.