“When we planned to start the China Mobile Big Cloud Elastic Computing project in 2009, we compared several most famous open source projects at that time. At last, we choose OpenNebula as our base for its clean structure and codes, clear documents, and ingenious design. The following years witness Opennenbula’s accelerated development and mature, which also prove our choice. As one of this community, we will continue to contribute the codes and functions, based on our optimization and extension for Chinese IaaS Cloud practices back to OpenNebula community and hoped to make our Elastic Computing project grow matured with OpenNebula.”

“I am impressed with OpenNebula mainly because:

• it is very simple to use, very sophisticated, but yet, you guys make it look very simple to implement & deploy (not the advanced deployment) as opposed to OpenStack
• less control traffic between the controller and the compute nodes (e.g.: no DB connection required)
• Sunstone has far more features integrated than Horizon (especially vm network provisioning)
• minimal configuration/setup in each compute node (pretty much ssh access, and a bit admin work)
• superb support from developers
• great resource/documentation
• the upgrade process is not scary!
• easy to pass init scripts to VMs
• well blended with openvswitch”

“For our internal Open Source Cloud lab environment we looked at several cloud solutions and finally zeroed in on OpenNebula because of the advantages offered in terms of quick server provisioning, easy to host cloud for internal development and educational purpose, flexibility and community support. In fact we tried a hitherto unknown scenario of using nested hypervisor in OpenNebula cloud, the details of which can be found on the OpenNebula blog.”

“We chose to implement OpenNebula on some customer’s projects because we found it stable, easily extendible and a commercial support is available if needed. It is platform independent, interoperable, based on open standards and APIs and can be used to build any type of IaaS cloud from private to public or hybrid. It includes advanced functions like centralized management of multiple hosting zones and supports on-demand provisioning of virtual data centers as well as features like fine-grained ACLs, X509 certificates or LDAP repositories that one can use to implement secured cloud platforms. Last but not least, multiple UI are provided for regular users or administrators.”

“OpenNebula was the best solution for our multi-customer and multi-hypervisor cloud platform. The different underlying data sources allow us to choose the best persistence layer to suit each customer. Using virtual data centers, we can bundle our customer and core resources, providing a flexible and reliable open source cloud solution. Best of all, with OpenNebula we can combine multiple platforms and system architectures from various vendors in a single solution.”

“The FermiCloud evaluated several open-source cloud management software packages in the course of our project. We chose OpenNebula for the scalability, reliability, and flexibility that it had. It was at the time, and remains, the best software for creating and managing the types of virtual machines that we do. The OpenNebula developers have been very cooperative in giving us advice and in accepting the authorization and authentication patches that we have submitted to the project. We have been running OpenNebula in a stable state since November of 2010 on a cloud that has as many as 200 virtual machines. We are now deploying a high-availability installation that extends across multiple data centers.”

“At Engineering Department, CERN we have been evaluating various cloud platforms such as Eucalyptus, OpenStack, OpenNebula and LabManager from VMWare to deploy control system applications on a private cloud to test and develop Large Hadron Collider (LHC) applications. After number of evaluations, we decided to deploy our private cloud with OpenNebula as cloud manager and integrating it with Swift Image Management tools from OpenStack and ESXi hypervisor. This flexibility of OpenNebula platform to be customizable was the key motivation for us to use it in our environment where our requirements were to use distributed storage on our cluster, public IP networking for our VM's and having a dashboard for our users to request VM's. And having a support license from OpenNebula made a big difference as the engineers on their side provided us with the necessary insight to make the changes to the code base.”

“Open means just that. It's not a cool marketing buzzword. OpenNebula captured my interest for several technical reasons besides the fact that it is truly open. It's architecture is very elegant; it has C++ bones, ruby muscles and bash tendons. It's extensible and understandable. It has no peer as far as I can tell.”

“The European Space Agency has large interest in Cloud Computing technologies for its heavy scientific processing; specially in the area of remote sensing and image processing. OpenNebula offered a smart middleware solution combining flexibility, scalability and excellent technical support for that purpose. Using OpenNebula, the Agency has been able to federate computing resources from different facilities and providers with a transparent and effective manner. OpenNebula is an example of European technical excellence.”

“SARA created its High Performance Computing Cloud infrastructure to allow Dutch scientists to get access to a fast and scalable cloud computing environment. Using open-source software for the complete IaaS stack enabled us to create a solution that allows the users complete control of their own environment. Using OpenNebula as the Cloud Data Center Management Solution we were able to modify the HPC Cloud to both the needs of System Administration and the Users of the Cloud. OpenNebula's completely open source model made extensions “deep” into to code possible and the open-source web-front-end Sunstone provided by OpenNebula was modified to integrate these extensions that are essential to our operations.”

“In past we had a simple virtualized infrastructure and we choosed to create a cloud to improve redundancy and scalability. We used OpenNebula because is easy to understand, to customize and to integrate in our billing process. We use OpenNebula 3.2 with Xen 3.3 Hypervisor and MooseFS storage with shared driver.”

“The project started from a state-of-the-art analysis focused on technologies available through open-source licensing. The frameworks selected at that time were Eucalyptus and OpenNebula (OpenStack was too immature); however, OpenNebula seemed more suited to the purposes of the project; we can summarize the reasons here:

• Compliance to the 'de-jure' standards, together with the 'de-facto' ones;
• Ability to implement hybrid clouds;
• Pluggable architecture by writing drivers even for the basic services (virtualization, storage, monitoring, etc.)
• Software package engineered as a single entity with a coherent architecture, and not like a simple compilation of existing products”

“During the architectural design of our CloudWeavers product, we have performed a long and detailed analysis of the available OSS cloud toolkit available, using our experience in previous EU research project devoted to OSS code analysis. We found out OpenNebula to be the most stable, mature and feature complete toolkit of all those surveyed by a large measure. Not hampered with the forced constraints of being another Amazon AWS clone, OpenNebula shines for its simple and transparent structure, well defined components and strong documentation. The responsiveness and open development approach of the project matches well with our largely open source-based approach, and has demonstrated over and over its effectiveness in adapting the software to many different use cases. CloudWeavers (and thus OpenNebula) is now in use in several installations, ranging from a few to more than 15,000 users, and never let us down a single time. There are no hidden or for-pay features, the documentation is excellent, and as a product never let us down a single time.”

“Initially we worked with OnGrid Srl to develop their colud infrastructure with OpenNebula. After about one year of collaboration with OnGrid, we created our cloud in another datacenter with the primary scope of serving internal requests of our system engineers and developers and with the secondary idea to provide geographic redundancy of OnGrid cloud for important applications. We choosed to use OpenNebula also on our infrastructure primary for the success-story on OnGrid cloud: it's easy to admin, clean to understand, easy to customize; OpenNebula is written in Ruby language and it's the primary language for our developers. Last but not least, oZone server helps us a lot in integration of two separate clouds infrastructure, an unique out-of-the-box feature!”

“The main reasons why our customers and prospects might decide to use OpenNebula cloud be listed as follow:

• The enterprise grade support through the affordable offering for subscribers.
• The most mature open source data center engine.
• The ability to manage existing VMware ESX and reduce costs and eliminate the need to use vCenter.
• The ability to access virtual resources which reside on top of ESX family through EC2 and OCCI APIs.
• The ability to build true hybrid clouds through EC2 und OCCI interface.
• The best self service interface provided through Sunstone to end users and administrators.
• Support for multiple storage backends from the same host.
• The ability to use the Virtual Appliance Marketplace and to contribute ready to use appliances from the community to the community and interact with the Marketplace through Sunstone.
• The best in class HPC support for telcos and research institutes.
• A great support team at C12G Labs which understands their community, customers and partners needs.”

“Terradue's Cloud Controller solution aims at brokering computing resources from different facilities and providers, and delivering a flexible and scalable hybrid Cloud environment to our customers. OpenNebula is the perfect baseline for such a product. It provides with an end-to-end approach and powerful customization capabilities, notably matching our accounting requirements. We also leveraged the OpenNebula pluggable architecture for writing Cloud API drivers, and benefitted from a reactive support, enacting a fully effective collaboration within our developments' timeframe.”