Category: Fabric

One of my friends wanted to design a nice-and-easy layer-3 leaf-and-spine fabric for a new data center, and got blindsided by a hyperconverged vendor. Here’s what he wrote:

We wanted to have a spine/leaf L3 topology for an NSX deployment but can’t do that because the Nutanix servers require L2 between their nodes so they can be in the same cluster.

I wanted to check his claims, but Nutanix doesn’t publish their documentation (I would consider that a red flag), so I’m assuming he’s right until someone proves otherwise (note: whitepaper is not a proof of anything ;).

I published the last part of my Optimize Data Center Infrastructure series: build an optimized data center fabric.

To learn more about data center fabric designs, check the new online course or enroll into the Spring 2018 session of Building Next-Generation Data Center course.

I first met Pluribus Networks 2.5 years ago during their Networking Field Day 9 presentation, which turned controversial enough that I was advised not to wear the same sweater during NFD16 to avoid jinxing another presentation (I also admit to be a bit biased in those days based on marketing deja-moo from a Pluribus sales guy I’d been exposed to during a customer engagement).

Pluribus NFD16 presentations were better; here’s what I got from them:

Arista’s OpenFlow implementation doesn’t support TLS encryption. Usually that’s not a big deal, as there aren’t that many customers using OpenFlow anyway, and those that do hopefully do it over a well-protected management network.

However, lack of OpenFlow TLS encryption might become an RFP showstopper… not because the customer would really need it but because the customer is in CYA mode (we don’t know what this feature is or why we’d use it, but it might be handy in a decade, so we must have it now) or because someone wants to eliminate certain vendors based on some obscure missing feature.

After explaining the challenges of data center fabric deployments, Dinesh Dutt focused on a very important topic I covered in Week#3 of the Building Network Automation Solutions online course: how do you separate data (data model describing data center fabric) from code (Ansible playbooks and device configurations)

Third vendor in this year’s series of data center switching updates: Cisco.

As expected, Cisco launched a number of new switches in 2017, and EOL’d older models … for pretty varying value of old. For example, most of the original Nexus 9300 models are gone.

One of the design scenarios we covered in Leaf-and-Spine Fabric Architectures webinar is a pure layer-3 data center, and in the “how do I do this” part of that section Dinesh Dutt talked about the details you need to know to get this idea implemented on Cumulus Linux.

We covered a half-dozen design scenarios in that webinar; for an even wider picture check out the new Designing and Building Data Center Fabrics online course.

Second vendor in this year’s series of data center switching updates: Brocade.

Not much has happened on this front since last year’s update. There was a maintenance release of Brocade NOS, they launched SLX series of switches, but those are so new that the software documentation didn’t have time to make it to the usual place (document library for individual switch models), it's here.

In any case, the updated videos (including edited 2016 content which describes IP Fabric in great details) are online. You can access them if you bought the webinar recording in the past or if you have an active ipSpace.net subscription.

In the past 5+ years I ran at least one Data Center Fabrics Update webinar per year to cover new hardware and software launched by data center switching vendors.

The rate of product and feature launches in data center switching market is slowing down, so I decided to insert the information on new hardware and software features launched in 2017 directly into the merged videos describing the progress various vendors made in the last years.

There are two reasonable ways of building a layer-2 leaf-and-spine fabric: use VXLAN (the direction almost everyone in the industry is taking at the moment), or routing-on-layer-2 technology like TRILL or SPB.