VMware NSX-T – What it is and why it matters
Nicholas Farina
Senior Technical Consultant

Highlights from the 2021 VMware EMPOWER Europe event

VMware the Network Vendor
VMware is not one of the first names that springs to mind when one thinks about major networking vendors, but perhaps that deserves a re-think. NSX for vSphere, commonly known as NSX-V or simply “NSX” was released way back in 2013, following its acquisition from little-known network software company Nicira, who had been developing it – under the name “NVP” – since 2007.

Back then, VMware was, of course, already successfully integrating virtual networking into its core vSphere product through the use of Distributed Virtual Switches; at the time a revolutionary step in server and desktop virtualisation that allowed multiple hypervisors to share a single network switching configuration.

NSX-V took this one step further by allowing additional network functions such as routing, firewalling and load balancing – traditionally powered by dedicated hardware devices – into a software-defined network configuration that could span multiple hypervisors. Not only did this promise to free companies of the inflexibility and spiralling support costs of hardware-based networking, but – through integration with the vCenter Server API – brought with it a level of interoperability with critical business services – such as antivirus, application segmentation and DR – that was hitherto unseen.

A new breed of networking – Software-Defined Networking or SDN – was born and with it came the beginning of the end for “pizza box” networking. Fast forward ten years and all of the major network vendors have their own SDN product – Cisco with ACI, Alcatel-Lucent’s CloudBand and so on. But if you trace these products back to their roots all were bought in by their respective vendors during or after 2013 - VMware were one of the first to the Network Virtualisation party and, as a result, their product is today one of the most mature in the industry.

A changing world
VMware vSphere is ubiquitous – today used by more than 400,000 companies, including 100 percent of Fortune 500 and Fortune Global 100. It runs 80% of the world’s VMs. While NSX-V was certainly successful- currently deployed by over 5,000 companies, it is perhaps surprising that it is not more widespread. While VMware is undoubtedly the “gold standard” in compute virtualisation, companies continue to favour a clear demarcation between their virtualised compute and storage systems and their predominantly hardware-based networks. Let’s face it – no one was ever fired for buying Cisco…

But things are changing, and with the world re-opening for business following the COVID-19 pandemic, the sun is rising on a Hybrid Cloud future.

92% of enterprises have a multi-cloud strategy and many of the data centre hardware refreshes we’re undertaking in 2021 are – unsurprisingly - smaller in scope than those conducted five years ago. In some cases they are a “stop gap”, intended to allow them time to plan a move of their Virtual Machines to the public cloud, or allow their key software vendors time make their products cloud-native.

In the same breath, customers acknowledge that some workloads – such as time-critical automation and control applications, legacy applications and applications that need to be kept close to their users for security or performance reasons, will likely need to run on-premises for the foreseeable future and the period of parallel running on-premises and cloud workloads could easily become decades long.

Meeting the hybrid cloud challenge
With applications split over the data centre and cloud – sometimes multiple clouds – network managers are left with a significant challenge – how do they maintain a consistent networking experience across the “old world” of hardware-based data centre networking and the “new world” one of software-defined networking in the cloud? How do they make sure these two completely separate environments are kept up to date with changes in application landscapes, constantly changing security requirements and protection against ever more sophisticated network security threats without “doubling up” on their already formidable workloads?

Is it possible to make a change to a firewall rule, allow access for a new server, application or data connection, or connect a new group of users with a single administrative change that would take effect everywhere – on prem and cloud, primary and DR, test/dev and production – without duplication of effort and multiplied risk of outage?

What is NSX-T and why does it matter?
NSX-V was a powerful product but was limited by its dependency on vCenter Server. Extending NSX virtual networks into the cloud and getting that crucial single point of management was complex and costly as extending NSX-V into the cloud meant using services such as “VMware Cloud for AWS” – effectively dedicated ESXi servers running in AWS datacentres, which were very costly and beyond the budget of many companies. And of course, integration of hypervisors other than VMware ESXi was impossible.

NSX-T, despite the similar name, is a completely different product, first released in 2017 and written “from the ground up” for hybrid cloud. The “T” in NSX-T stands for “Transformers”, as the product was intended to transform customers beyond simple on-prem network virtualisation with vSphere and into the realm of hybrid cloud and the software-defined data centre (SDDC).

As distinct from its predecessor, NSX-T is a completely stand-alone product with no dependency on vCenter Server. NSX-V used to “piggy back” onto VMware ESXi’s baked-in Distributed Virtual Switch software. NSX-T instead uses a “Host Transport node” – a special virtual machine that runs on top of the hypervisor and processes each and every packet of network traffic received and transmitted by the host. This “abstraction” or separation from the hypervisor’s core executables allows mismatched host versions and – for the first time – non-ESXi hypervisors to participate in an NSX network, while faster modern CPUs make the additional abstraction indistinguishable from a performance point of view.

At the time of writing, is the most current version of NSX-T Data Centre. This supports the following hypervisors:

Hypervisor Versions
vSphere ESXi 6.5U3 and above
CentOS Linux KVM 7.6 and above
RHEL Enterprise Server KVM 12 SP3, 12 SP4
Ubuntu KVM 1.04, 18.04.02 LTS

See here for the full interoperability grid.

This cross-platform compatibility is what allows NSX-T to at last offer a true multi-cloud software-defined network with a single point of administration.

Even the NSX Manager, the user’s point of administration via GUI, CLI and API, can run on a KVM hypervisor, meaning that a customer could use NSX without vSphere or ESXi at all if they wanted to, or manage their whole network – cloud and on-prem – from within the cloud.

NSX-T Data Centre now integrates fully with the vCenter Client and carries across key NSX-V features, such as:

3-Tier architecture – management, control and data planes with full redundancy at each level
Micro-segmentation to limit unwanted and risky East-West traffic between servers
In-depth, workload-aware network monitoring and predictive analytics
Advanced “goes-everywhere” routing and firewalling services
Automated scaling
Access control for containers
“One-button” spin-up of entire network environments for test, development and UAT
API-based Integration with other services, such as Antivirus and DR
And more.

VMware are so sure of NSX-T Data Centre that they have announced the phasing out of NSX-V. VMware have declared that NSX for vSphere 6.4 (the last version of NSX-V) will no longer be supported after 16 January 2022, with end of technical guidance following one year after that. At the 2021 EMPOWER event, VMware showcased a rich suite of tools designed to assist NSX-V Customers in migrating to NSX-T Data Centre, which will be VMware’s sole network virtualisation product going forward.

This means that – in addition to those 5,000 companies we mentioned earlier, a further 14% of businesses in the US and Europe are considering deploying Network Virtualisation in the next two years.

For more information about how NSX-T can help your business, please contact us today to fix up a discussion with one of our experts.

Ultima's VMware Partnership
Ultima is regarded as one of the UK’s leading VMware partners, specialising in virtual network and security, cloud and DRaaS, NSX, server and desktop virtualisation, business continuity. We employ one of the highest numbers of VMware Technical Sales Professionals of any Partner within the UK.

VMworld Highlights Virtual Event
VMworld is designed to help you welcome change, to realise a world with more options and less complexity, more automation and less overhead, more choice and no compromise. Taking place on 6-7th October, register for your free pass to the industry's premier multi-cloud event.

Following the event, we'll be hosting a VMworld Highlights Virtual Event to cover the key takeaways and help you gain the knowledge you need to help your organisation evolve its technology strategy. As we can't be together, we'll be bringing the experience to you by sending you some drinks and nibbles to enjoy during the session. 


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