The evolution of today’s data centre networking demands requires massive compute power. To handle the increased classic server to client north-south traffic. Plus the new east-west, machine-to-machine communication that occurs within the data centre and public and private clouds.
Enterprises are embracing new software-defined concepts and complementary technologies that have been developed to take full advantage of the promise a virtualised software-defined data centre (SDDC) holds. It’s a complex path to achieving a fully virtualised hybrid IT environment, but worth taking given the performance, agility and cost benefits. Here are some of the major concepts and technologies needed to move forward:
Also known as software-defined compute, computer virtualisation is the fundamental technology SDDC is based on. It requires x86 servers and has become the industry-standard technology. Traditionally, deployed servers use only around 10 to 15% of their capacity. Virtualisation decouples memory and CPU from physical hardware, allowing those unused resources to be used wherever they’re required.
In brief: computer virtualisation increases server efficiency, delivering higher performance and higher availability, all at a lower cost
A fundamental piece of computer virtualisation technology is the hypervisor. This piece of software lets physical devices share their resources among VMs running as guests on that physical hardware, or host machine.
In brief: there are three types of hypervisor:
- Bare-metal installation – the first piece of software to be installed on the server as the operating system. It also becomes the hypervisor.
- Hosted hypervisor – software is loaded on top of an already existing operating system.
- Guest machine (also known as a virtual machine) – the workload that’s installed on top of the hypervisor.
The whole point of a container is to run a single application. The more functionality you stick into a container, the more likely it is you should’ve been using a virtual machine (VM). Each VM runs not just a full copy of an operating system, but a virtual copy of all the hardware that the operating system needs to run. This quickly adds up to a lot of RAM and CPU cycles. In contrast, all that a container requires is enough of an operating system, supporting programs and libraries, and system resources to run a specific program.
In brief: use containers to run a single application and VMs to run multiple applications.
SOFTWARE DEFINED STORAGE (SDS)
SDS is storage deployed as software. Applications and underlying storage services share hardware resources. SDS is the second step, behind software-defined compute, to achieving an SDDC infrastructure. To leverage SDS you can use a cost optimising approach with virtual storage appliances or employ a service-level optimisation approach that uses a dedicated, virtualised multi-tenant system.
In brief: SDS is highly scalable and housed on industry-standard servers, and allows you to do away with dedicated arrays.
SOFTWARE-DEFINED NETWORKING (SDN)
SDN lets network administrators manage network services by abstracting lower-level functionality. It accomplishes this by decoupling the control plane, which is the system that decides where traffic is sent, from the data plane, which is the underlying system that forwards traffic to the selected destination.
In brief: the network control becomes directly programmable, and the underlying infrastructure can be abstracted for applications and services. Other benefits include increased network agility and the ability to centrally manage it. Implemented through open standards, it becomes a vendor-neutral, standards-based proposition.
NETWORK FUNCTIONS VIRTUALISATION (NFV)
NFV uses virtualisation technology to decouple network functions and create individual virtualised network functions (VNFs) that IT can connect as desired. A VNF consists of VMs, or containers, running different software and processes on top of standard infrastructure, rather than having hardware appliances for each network function. NFV is similar to SDN but different. It is not dependent on SDN, so you could potentially employ a VNF on existing networks without SDN.
In brief: performance and cost benefits in an SDDC are clear, and several vendors are developing NFV / SDN platforms.
The SDDC is not simply a stop on the way to a fully cloud-deployed infrastructure. Rather, SDDC is absolutely on the path to cloud, and cloud is a key part of the future of the data centre. We partner with Hewlett Packard Enterprise, a world leader in technology, inspiring innovators and entrepreneurs across the globe with their server, storage and software solutions.
How Hybrid IT Enables the Software-Defined Data Centre’ taken from article entitled ‘How Hybrid IT Enables the Software-Defined Data Centre’ which appears in HPE guide entitled ‘Foundations of Hybrid IT’.