In modern days, many varieties of tools are available for developing and managing cloud environment. OpenNebula is one such open source collection of tools for cloud computing and data centre virtualization and it comes free of cost. The biggest highlight of OpenNebula is its capability to manage heterogeneous infrastructure. It can be used to create public, hybrid and private cloud environment; due to which it is considered an IAAS [Infrastructure as a service] cloud solution. It deploys multi-tier services as virtual machines on disturbed infrastructure and enhances technologies like security, networking, storage, virtualization, and monitoring. Also, it offers cloud user and administrators choices of interfaces. As it is an open source technology, OpenNebula is distributed under the Apache License 2

In order to develop, build and manage data centre virtualization and enterprise clouds, Open Nebula is a flexible and feature rich solution. Using different Hyper-V and storage systems OpenNebula can centrally monitor and administer virtual systems. It can stop a large extent of issues due to hardware failures by taking care of the virtual instances on a different host system. Without any further hardware investment the integration and automation of existing heterogeneous environment is flexible using OpenNebula.

OpenNebula becomes the ideal solution for heterogeneous computing centre environment because of the plurality support to platform independent architecture and Hyper-V. The benefits of OpenNebula include:

• OpenNebula is available for all major Linux distro’s and it is easy to install.
• It proves it stability and flexibility in long term and large scale production environment.
• It is 100% free of cost and all the features are available in a single edition.
• It controls, manages and develops via web interfaces and command line.
• OpenNebula supports and is interoperable with AWS [Amazon Web Service] and OCCI [Open Cloud Computing Interface].

Key features of OpenNebula include:

• Scalability
• Integration
• Security
• Accounting
• Supports standardisation, portability and Interoperability.
• It provides ability to choose several cloud platforms or interface for cloud admin or user.

Coming to the architecture of OpenNebula, it has core coordinates to control the VM’s life cycle. Following are the main components of the same:

• Network Fabric: To create the virtual network environment.
• Hypervisors: For creating, deploying and controlling VM’s.
• Image and storage technologies: To create disk images.

OpenNebula has pluggable drivers through which it coordinates all these operations. There is also a separate scheduler component to manage the VM placement and it follows a ranking schedule policy for deploying VM’s. Ranks are allocated based on the ranking algorithm and also the scheduler works completely based on the ranking algorithm. The communication between OpenNebula and external cloud environments are drawn using the cloud drives defined by default. The management interface helps OpenNebula to integrate control over external management tools.

Components of OpenNebula include:

• Users and Groups: Similar to user and group in Linux, OpenNebula also permits user and group definition and allocation of different permissions to each of them.
• Hosts and VM resources: As you know these are the key aspects of heterogeneous cloud that are monitored and managed.
• API’s and interfaces: These are used to control and manage the OpenNebula components, mainly the interaction between the physical and virtual interfaces.
• Storage Components: These are template repositories.
• Network Components: Flexible and it mainly uses Open vSwitch and VLAN’s