The Nimbula Cloud Operating System is an automated cloud management system delivering Amazon EC2-like services behind the firewall. Nimbula's technology allows customers to easily repurpose their existing infrastructure and build a computing cloud in the trusted environment of their own data center. Using simple and rapid deployment technologies, The Nimbula Cloud OS transforms under-utilized private data centers into muscular, easily configurable compute capacity, quickly and cost effectively. With access to both on- and off-premise cloud services available via a common API, the Nimbula Cloud OS combines the benefits of capitalizing on internal resource capacity and controlled access to additional external compute capacity.

The Nimbula Cloud OS technology has been designed to uniquely respond to the following key requirements of an enterprise cloud solution:

• Scalability – The Nimbula Cloud OS is designed for linear scaling from a small cluster up to hundreds of thousands of computers. This allows an organization to grow and grow quickly.

• Ease of use – A highly automated, hands-off install requiring minimal configuration or interaction dramatically reduces the complexity of deploying an on-premise cloud. Racks come online automatically in under 15 minutes. Management of cloud services is largely automated, significantly improving operational efficiency.

• Ease of migration – The Nimbula Cloud OS facilitates easy migration of existing applications into the cloud through its support for multi-platform environments and flexible networking and storage.

• Flexibility – The Nimbula technology supports controlled federation to external private and public clouds like Amazon Elastic Compute Cloud (EC2) as needed by the customer: during peak times or for specific applications.

• Reliability – With no single points of failure, the Nimbula Cloud OS employs sophisticated fail over mechanisms to ensure system integrity and resilience.

• Security – A robust and flexible policy based Authorization System supporting multi-tenancy provides mature and reliable security and sophisticated cloud management control.

The Nimbula Cloud OS provides the following set of key features:

• Self-healing and self-organizing – Robust fail over mechanisms, including monitoring of services and nodes and automated service replacement, ensure system reliability and resilience.

• Flexible and powerful group-based Authorization Service – Fine-grained permissions management based on policy supports advanced access control of multiple users and groups.

• Multi-tenancy – The Authorization Service allows multiple customers, groups and users to co-exist in isolation from each other or share resources on a single site.

• Federation – The Federation Service supports request forwarding to external sites, such as public clouds, subject to Nimbula’s fine-grained permissions management. This authorization filter facilitates powerful control and access management currently unavailable on public cloud offerings. The Federation Service provides a uniform API interface to both local and remote private and public clouds.

• Sophisticated placement – Instance placement can be specified with respect to the type of machine on which the instance should run and the proximity to other instances, including whether instances should run on the same or a different node or cluster. This is useful when providing redundancy, where for example it wouldn't be desirable to launch a fail over database server instance on the same physical machine as the original database server. Instance proximity also impacts on network performance with close instances providing lower-latency, higher bandwidth and more reliable connectivity.

• Integration with existing user services – Nimbula's Authentication Service supports Active Directory/LDAP, facilitating hassle free user management and the efficient reuse of existing corporate user databases.

• Advanced networking – Besides supporting flat standard IP allocation, the Nimbula Cloud OS allows customers to create and declare their own virtual ethernets. This enables the launching of instances in multiple isolated layer 2 networks where customers may provide their own DHCP server and other layer 2 services, such as multicast broadcast and non IP ethernet protocols. Applications may be assigned to network security groups and have security policy enforced independently of the underlying network topology. This eliminates the complexity of porting applications that rely on layer 2 communication into the cloud as they can run unmodified.

• A clean 'network' API – A RESTful HTTP API with JSON encoding supports a rich set of functionality and a simple and robust interface to cloud resources.

• Dynamic storage allocation – Storage volumes can be created and deleted via the API and these volumes can be dynamically attached and detached from instances. The ability to automate disk allocation as needed increases operational efficiency by removing the dependence on system administrators to perform disk allocations.

• Integrated system metrics and reporting – All requests, incidents and events are subject to comprehensive recording and reporting, providing a rich audit trail and detailed graphical summary of cloud status in near real time.

• All Xen or KVM compatible operating systems supported – KVM and Xen hypervisor technologies provide support for compute instances running a wide variety of operating systems, including Microsoft Windows, Linux, Solaris, BSD and AIX. Existing applications running on a wide range of operating systems can easily be moved to the cloud as Nimbula supports a host of guest operating systems.

The Nimbula Cloud OS abstracts the underlying technology to provide a coherent view of a completely automated virtual data center. Nimbula's intelligent cloud control software isolates customers from the operational and hardware complexity associated with deploying compute in a static private data center. Facilitating the rapid deployment of enterprise grade compute into the cloud and dynamically managing workload allocation, the Nimbula technology transforms data center management.

A RESTful HTTP API provides a simple and comprehensive interface to all aspects of cloud resource control. Cloud resources can also be managed via a command line interface (CLI) and web control panel, built on top of the API.

Beneath the virtual data center abstraction sits a physical layer of storage, network and compute hardware managed by multilayer control software. Nimbula integrates a hypervisor* (KVM and/or Xen) with node management software on each node to achieve automated deployment and configuration.

Compute Control
The cluster is the compute backbone of the Nimbula Cloud OS and consists of a number of x86 based computers, referred to as nodes, connected to a network. All nodes are controlled by the Infrastructure Controller (IC) which ensures that all services run correctly across the cluster at all times.

It is the IC, which runs as a distributed service across all nodes, that enables the cluster to be self-healing and self-organizing. At any one time one node is designated as the IC master, a number are designated as IC submasters and the rest act as IC workers. The IC master delegates tasks to IC workers to start and stop services and along with IC submasters, receives notifications of service state changes. In the case of the master failing, the submasters quickly become aware of the failure and elect a new IC master, ensuring system resilience.

Storage Control

• The Nimbula Cloud OS is compatible with various storage services including third party enterprise solutions from vendors like EMC and NetApp and open source solutions employing technologies such as LVM, DRBD and Open-iSCSI.
• Nimbula's Cloud OS Storage Control allows users to dynamically create and delete virtual storage volumes and associate these with instances anywhere. Users have fine control over the placement of their storage in the cloud so as to manage contention, performance and fault tolerance with respect to attached instances.
• Storage capacity can easily be added on demand and is automatically incorporated into the storage control system.

Network Control

• The Nimbula Cloud OS facilitates the creation of highly dynamic virtual network topologies, independent of the underlying network topology.
• The Nimbula Cloud OS provides fine-grained security based on policy instead of network topology.
• Users are able to dynamically create virtual ethernets (vEthernets) using existing networking and associate these with instances using virtual NICs (vNICs). Full layer 2 functionality, including broadcast, multicast and non-IP traffic is supported.

Monitoring
The Nimbula Cloud OS gathers and collates monitoring information which can be accessed via a web interface and integrated with monitoring software.

Dramatically improving the scale and efficiency of server and application provisioning while reducing application deployment cycle times and accelerating innovation, the Nimbula Cloud OS provides the following key benefits:

• Reduce application deployment time by allowing virtual compute instances to be launched in minutes as opposed to hours or days.
• Increase infrastructure utilization rates especially where load is variable.
• Increase the rate of innovation by providing new opportunities for innovation through increased infrastructural flexibility.
• Reduce operational overheads by dramatically reducing the demand on data center system administrators.
• Controlled integration with public cloud services by allowing customers to tightly control the deployment of services into external clouds.

Cloud computing offers the promise of highly scalable infrastructure with greater flexibility and dramatically lower costs. The Nimbula Cloud OS brings these values of scale, low friction and lowest cost to the private data center. Differentiated by high levels of automation, flexibility,control, scalability, security and resource accountability, the Nimbula OS provides the complete utility-grade cloud management solution.

* A hypervisor allows multiple operating systems to run concurrently on a host computer effectively providing hardware virtualization.