Understanding Eucalyptus in Cloud Computing: Building Private and Hybrid Clouds

Eucalyptus is an innovative open-source solution for building private and hybrid clouds within the Amazon Web Services (AWS) framework. Standing for Elastic Utility Computing Architecture for Linking Your Programs To Useful Systems, it offers a way to create a personalized data center in a private cloud. In this article, we delve into what Eucalyptus is and its main components in cloud architecture.

What is Eucalyptus in a Cloud Environment?

Eucalyptus allows the creation of a private cloud by pooling computing and storage resources to scale up operations effectively. It enables users to create images of software applications, which are then deployed to create instances for computing needs. Notably, a Eucalyptus instance can possess both public and private IP addresses, enhancing its flexibility and application.

Main Components of Eucalyptus Cloud Architecture

The Eucalyptus cloud architecture comprises several key components:

  • Cloud Controller (CLC): This Java program with a web interface manages virtual resources like servers, networks, and storage. It’s at the top of the hierarchy, handling tasks like resource scheduling, system accounting, authentication, and quota management.
  • Walrus: Equivalent to AWS S3, Walrus is a Java program providing persistent storage and hosting images, volumes, and snapshots.
  • Cluster Controller (CC): A C program that acts as the frontend for a Eucalyptus cloud cluster, managing instance execution and communication with the Storage Controller and Node Controller.
  • Storage Controller (SC): Similar to EBS in AWS, this Java program interfaces with the Cluster Controller and Node Controller to manage persistent data via Walrus.
  • Node Controller (NC): This C program hosts virtual machine instances, downloading images from Walrus to create instances for computing requirements in the cloud.
  • VMWare Broker: An optional component providing an AWS-compatible interface to the VMWare environment.


Eucalyptus offers a robust framework for organizations looking to leverage the power of cloud computing within their own private or hybrid cloud environments. By understanding its components and capabilities, businesses can effectively utilize this platform to meet their specific computing needs.