Cisco Blogs


- February 1, 2008 - 2 Comments

As I Google”Cisco Nexus” and look through the articles, it is a rare article that doesn’t mention the”15 terabit” number within the first couple of sentences. I can certainly understand this because its a sexy number and its an easy way to quantify the engineering goodness baked into this platform. But, to be honest, if, after spending all this time, money and effort on a new platform, all we could talk about was speeds and feeds, it would be a little sad.Ironically, the reason I think folks will want a Nexus are a couple of areas that have not gotten much press so far. The first of these”secret weapons” is NX-OS, which has actually been a source of some trepidation. So, first off,”new” is a bit of a misnomer. What we did was start with the proverbial clean sheet and design an OS explicitly for the data center. We had the latitude and R&D capability to cherry-pick from the Cisco technology pantry and build from scratch as appropriate. So, we chose SAN-OS, which has been running for over 4 years in some of the most demanding enterprise data centers out there, as the foundation. Likewise, our layer 3 code, from our Procket acquisition, has been deployed with several major service providers for a number of years. Finally, our layer 2 code was written with the same team that made the Catalyst so successful.As you can see, we took a very modular approach to building the OS, which is one of the reasons we can successfully integrate these components. In fact, I believe that the fact that NX-OS is a extremely granular and modular OS built atop a secured Linux kernel will appeal to the vast majority of customers. If offers a number of advantages in terms of flexibility, stability and extensibility that other folks will be hard pressed to meet. And, by the way, we wrapped all this in an IOS-like CLI so ramp-up time for staff is minimal. OK, I’m a bit biased, but I think we have hit the mark in terms of giving you operational and functional consistency with the existing Catalyst family, while also giving you an OS that will grow with you the next decade or so.But we’re not done yet. The framework of NX-OS also allows us to break new ground in terms features and functionality. One of the coolest new features are Virtual Device Contexts (yes, the engineers named this one). The NX-OS brings hypervisor-like functionality to the Nexus, so you can deploy multiple virtual switches on a single physical platform. This lets you support multiple environments on a single switch, say dev and production, or different lines of business with different business polices. VDCs also allow you to segment your environment to keep your security and compliance folks happy. In short, VDCs allow you to drive higher return out of your investment through more efficient utilization and greater flexibility.That’s about it for now-you can go to for more details. Next time, I’ll dig into exactly what”zero service disruption” means.

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  1. Henry:Thanks for your interest. I hate to give you an ambiguous answer, but it really depends on a couple of factors. Currently VSS is only available on the Catalyst 6500, but eventually you will see similar functionality in in the Nexus family too.Beyond that that, it depends on what the other functional requirements are gong to be. A couple of questions to answer early on: 1) how do you want handle services (Nexus does not currently support service modules) and 2) what are you doing with your servers in the long-term--if you are looking at a broad-based move to server virtualization and/or 10GbE attached servers, Nexus might be a better bet, since it is optimized for a 10GbE environment. As you probably know, DC design is a complex endeavor, so offer up these questions simply to get the ball rolling.One approach might be to take advantage of our lease specials which allow you to get a Cisco 6500 now, and move to a Nexus 7000 any time after 12 months (the balance of your lease payments are forgiven). Check this link for details:"

  2. So If I want to buy a switch for my data center, which platform is more suitable to me ? 6509 with vss or Nexus 7000 ?I hate STP,so vss can get rid of it. How about Nexus ?thanks!