Hyper-converged infrastructure

Hyper-converged infrastructure (HCI), also called a hyper-converged integrated system (HCIS), refers to a type of virtual computing platform that natively converges compute, virtualization, and storage into a single software-defined architecture, frequently used in a data center. The single piece of software interacts with each of the components and the underlying operating system.

It is similar to converged infrastructure (CI), but with the addition of storage. However, in converged infrastructure, the individual components of storage, compute, and networking are not natively controlled by a single software architecture as in HCI. Each component in CI has it's own controlling software between it's hardware and the underlying operating system.

At a high level, hyper-convergence can support common data center availability and reliability requirements, infrastructure is managed and workloads are deployed through a single interface to the underlying operating hardware. The difference between converged and hyper-converged infrastructures is that the building blocks of each of the subsystems in converged infrastructures are discrete; the server is separate and used as a server, just as the storage subsystem is separate and used as functional storage.

Hyperconvergence moves away from multiple discrete systems that are packaged together and evolve into software-defined intelligent environments that all run in commodity, off-the-shelf x86 rack servers. Its infrastructures are made up of conforming x86 server systems equipped with direct-attached storage. It includes the ability to plug and play into a data center pool of like systems. All physical data center resources reside on a single administrative platform for both hardware and software layers. Unifying all platform types to one, together with single vendor management, eliminates traditional data center inefficiencies and reduces the total cost of ownership (TCO) for data centers.

HCI is the most popular method for acquiring the best-understood version of software defined storage (SDS). It is a fully packaged system expression of SDS. The terms should not be seen as synonymous, but they are closely related. The most well known SDS packages offer the software building blocks for integrating and deploying an HCI system. Some HCI systems also offer their software a la carte as SDS, but typically only for a limited range of chosen server vendors and configurations.

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