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Unifying VMware NSX-MH, NSX-V may be easier said than done

Merging VMware's two NSX code bases could save time and development costs. But significant architectural changes to the latest version could result in giving back some of those savings.

VMware has begun a potential long and difficult march toward unifying the two versions of its NSX networking product around a common code base.

With little fanfare this past May, the company made a significant refresh to the multi-hypervisor version of NSX, rolling out a new version called NSX-T to replace NSX-MH. The multi-hypervisor version of the company's network virtualization software supports the KVM, ESXi and Xen hypervisors, and was a holdover from VMware's purchase of Nicira and its Network Virtualization Platform in 2012.

However, with a raft of new features in NSX-T, upgrading NSX-MH users is not a simple in-place upgrade. Instead, it likely will involve a complete reinstall of the product, costing users more money and the work necessary to make technical adjustments to the existing environment.  Moreover, if the eventual goal is to merge the code bases of NSX-T with NSX-V, the latter easily the more popular of the two NSX versions, the reinstall process becomes an even bigger problem for VMware.

Upgrading from NSX-MH to NSX-T "will be more along the lines of a re-install," said Geoff Huang, VMware’s senior director of product marketing for NSX. "We want to make sure the design is improved because design makes sense when they move to [NSX-] T. It's not going to be an in-place upgrade from one version to another."

If users sense fundamental differences between NSX-V and NSX-T, it could spook existing NSX-V users from upgrading, and further delay purchasing decisions among first-time NSX users. Given the recent sales momentum and strategic importance of NSX-V, this is something VMware must sidestep.

"Anytime a vendor makes a significant change to their code there is some fallout," said one analyst who specializes in networking software. "Everyone in the networking business knows you don't want to run version 1.0. If I was a user, I would recommend waiting for two or three quarters for all the bug fixes to arrive."

The flagship version of the product, NSX-V, supports only VMware's ESXi hypervisor, but accounts for 90% plus of overall sales. VMware has publicly emphasized new updates to NSX-V, while saying little of its sales efforts or direction for NSX-MH. The current version of NSX-V stands at 6.2.3, while NSX-MH has seen less frequent updates, the latest being 4.2.6 which lacked many of the features available in NSX-V.  NSX-T release notes are not publicly available, but the product was given a 1.0.0 moniker in the limited references to the version on VMware's website.

NSX-T is the unified NSX code base

NSX-T, which VMware officials said is generally available now and gradually will replace NSX-MH as users migrate over, will serve as the unified code base of NSX-V and NSX-MH. In the meantime, VMware will continue to sell both NSX-V and NSX-T separately. VMware officials have indicated their goal is a single version of NSX, but precisely when and how it will arrive is unclear.

"The goal is to take the functionality in [NSX-]MH, take functionality in V, and create a product that is a superset of those two," Huang said.  "There will be additional things we do in T as well, but the goal is to be a superset of MH and the V."

The shipping versions of NSX-V and NSX-T do not have feature parity today, with each product containing functionalities the other lacks. NSX-T includes some features that were taken from NSX-V, such as distributed firewall, a high-performance N-S edge cluster supporting dynamic routing protocol, and multi-tier routing for clear separation between application/tenant specific routing.

"There are unique things we've developed for T," Huang said. "We wanted to convey this is not just a [dot update of NSX-MH], that it has some significant improvements from MH and from what we took from V." He added that "there will be more stuff we're going to be adding" in future versions, but would not specify what those added capabilities will be.

The idea of merging two different code bases has benefits for both users and IT professionals in terms of saving time and money when adding in new features and any costs associated with managing two platforms.

“If you are a vendor or user with two code bases to deal with, it is double the development effort in order to bring in new features," said Andrew Lerner, a vice president with Gartner Inc. "What you want is one code base split into two deployment options, but today they [VMware’s NSX] largely have two."

Do users need multi-hypervisors?

What is not so clear an advantage, to some, is the need to bundle multiple hypervisors into a single offering, except for extremely large IT shops with complex heterogeneous environments spanning on premises and cloud environments.

"I don't think users are demanding multi-hypervisors," said Tom Nolle, president of CIMI Corporation, a consulting firm focused on telecommunications and data communications. "If you're supporting a public or private cloud, you don't know what hypervisor will be demanded."

There is probably not going to be more than one hypervisor, except on a transient basis, and it's just going to raise your costs and complexity, Nolle added.

Others believe offering a single version of NSX, with at least the option to deploy any one of three different hypervisors -- two of which are not proprietary, namely KVM and Xen -- could open up new markets for not just VMware, but also for the newly merged Dell and EMC.

"In the context of the Dell-EMC merger, VMware is the on-ramp for what those two companies need to sell," said Dana Gardner, principal analyst with Interarbor Solutions, LLC, in Gilford, NH. "It would be smart of them to open up their products and stop trying to leverage their vSphere dominance in order to gain further dominance."

Some suggest VMware hasn't pushed the multi-hypervisor version of NSX to the broader market because it wanted to protect its flagship vSphere franchise, which appears to have plateaued over the past year or so. They feared bringing in support for KVM and Xen too soon would suck even more market share away from vSphere at the time when NSX-V appears to be finally taking off.

"One of the things that is characteristic about companies that have an incumbency is they take root and become a tree," Nolle said. "And that is what these guys (VMware) have done."

VMware executives should have realized long ago their chances of establishing VMware's platform as any sort of universal cloud architecture was unlikely to happen and they should have more aggressively supported competitive hypervisors, Nolle believes. Now the company has finally admitted that, he said, as evidenced by the multi-hypervisor support in NSX-MH and the fact they finally have their own version of OpenStack.

What has been missing so far in NSX-V, NSX-MH and now NSX-T is support for Microsoft's Hyper-V, which has steadily ripped market share away from VMware's vSphere over the past year or more. Its momentum doesn’t figure to slow much, either, with the upcoming Windows Server 2016 on the horizon which bundles in Hyper-V.

Some believe future versions of NSX would be greatly enhanced with support for Hyper-V, given the vast majority of IT shops that have both Windows Server and vSphere.

"If there were is to be multi-hypervisor support for Microsoft, I think that could change things," Gartner’s Lerner said.

VMware officials declined to say when or if the company would include support for Hyper-V in future versions of NSX -- only saying "it is on our roadmap."

Ed Scannell is senior executive editor at TechTarget. He can be reached at [email protected].

Ryan Lanigan, assistant editor, and Nick Martin, executive editor, contributed to this article.

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