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So What Exactly is a Nexus 4000?

October 6, 2009 - 10 Comments

Now this is not a rhetorical question. I want answers, folks, answers! In the past we posed such questions but answered them in the same blog post. I’d like to try a different approach, I would like our blog readers to post their initial impression & understanding of Nexus 4000 first. So go ahead & post.



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  1. All, Thanks for posting all the useful comments on this topic. I'm glad to see the interest in this solution. Pls see my comments and details on the follow-up blog below...,-Kash

  2. Here’s what I know about the Nexus 4000 switch:1) It will aggregate 1GB links to 10Gb uplink. To me, this means that it will not be compatible with Converged Network Adapters (CNAs). From this description, it seems to be just the Cisco Nexus 2000 in a blade form factor. It’s simply a “fabric extender” allowing all of the traffic to flow into the Nexus 5000 Switch.2) It will run on the Nexus O/S (NX-OS) This is key because it allows users to have a seamless environment for their server and their Nexus switch infrastructure.3) Cisco Nexus 4000 will provide “cost effective transition from multiple 1GbE links to a lossless 10GbE for virtualized environments” This statement confuses me. Does it mean that the Cisco Nexus 4000 switch will be capable of working with 1Gb NICs as well as 10Gb CNAs, or is it just stating that the traditional 1Gb NICs will be able to connect into a lossless unified fabric??

  3. What is the Nexus 4000? It is a product that finally answers the question - FCoE is great, but can I run it in my non-Cisco bladecenter?"" It is also a signal to the industry, that even though Cisco manufactures its own compute devices, it will not abandon other compute platforms network components.Last, but not least the Nexus 4000 is the final piece of the puzzle allowing a single NX-OS driven network operating system end to end in a data center."

  4. Hopefully, it is a blade switch variant of the N5K, which implies NX-OS, L2, 10G up- and downlinks, with the option of doing 1G on the downlinks, FC and FCoE support etc.Hopefully, it will be available for at least HP, IBM and Dell blade systems.Hopefully, the price for a Cisco-powered blade switch will this time be market conforming.Sadly, it may be a little too late to the party.

  5. Um .. here goes.The Nexus 4K is a Nexus switch in a blade form factor which can be OEM'd into Blade vendors product lines. First out the door for support is IBM. The N4K provides the benefits of Unified Fabric such as convergence, including FCoE and 10GE.Those who have been digging into UCS they may wrongly view this like an IOM (FEX) inside a UCS 5100 Chassis, being similar in function to a N2K Fabric Extender. However this would be wrong, the N4K is a full switch.Rodos

  6. Nexus 4000 is a 10 Gig blade switch for the 3rd party blade server chassis.

  7. Hi Kash,Some quick thoughts re Nexus 4000 - I see this as further confirmation of Cisco's determination to create, grow and dominate the CEE/FCoE market - and I dont blame them. Everyone else, with the exception of Brocade, is dragging their heels and will only have themselves to blame if/when Cisco ends up owning this market.Cisco struggled to oust Brocade at the top FC switch vendor so is making sure it gets ahead early in the CEE/FCoE space. It appears to be doing this by getting to market first with products, having the top bloggers and tweeters on the subject (except me ;-) as opening the game up to partners to integrate with their kit.Companies like HP with their ProCurve networking offerings are clearly lagging behind but have opportunities get involved in the market by reselling and integrating Cisco technology. If the Cisco kit works well enough with HP and IBM kit (e.g. plugging into HP BladeSystems) then will HP bother trying to develop ProCurve to compete, or will they decide its not worth the R&D effort and capital spend, and just decide to ship Cisco?On the day that the Nexus 4000 was shipped I asked HP if they would support it in their BladeSystems (obviously I wasn't asking the people who actually make those decisions, but they were fairly senior people) and the answer that I got was ever say never"".Personal opinion is that Nexus 4000 is a very interesting product and strategic move. 10Gbps CEE is on its way and Cisco are taking the bull by the horns so to speak. Can't wait to see one!Nigel"

  8. Kash,Nexus 4000 by Cisco is a switch in a blade server which for the first time allows a switch element between the server adapter (CNA) and the FCF (which is in the FCoE switch, such as the Nexus 5k boxes). I did a video that describes this which can be found at

  9. hmm, according to many sources on the Cisco web 'Sorry, the product/technology you selected does not have the requested documentation available.'Best guess, a Layer 2 blade switch version of Nexus 5000 without FC interfaces, supports 1 & 10 G connections.

  10. I guess I would frame this as a question to validate my understanding.Is the 4000 simply an easy to install 5000 in a package to fit inside a blade chassis to get its power?For instance does it do anything different than the 5000 like connect to the backplane network in the chassis? Are all the same ports and options still on the front panel as on the 5000?Basically, since it was so ho-hum I could not find any info on about it, so all I could gather is that its 'a 5000 that plugs into a blade chassis'.