Category: fabric

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.

First in line: Arista EOS. You can access the videos if you bought the webinar recording in the past or if you have an active ipSpace.net subscription.

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.

During Shawn Zandi’s presentation describing large-scale leaf-and-spine fabrics I got into an interesting conversation with an attendee that claimed it might be simpler to replace parts of a large fabric with large chassis switches (largest boxes offered by multiple vendors support up to 576 40GE or even 100GE ports).

As always, you have to decide between implicit and explicit complexity.

The work of editing transcripts of my two switches presentation is (very slowly) moving forward. In the fourth part of the Optimize Your Data Center Infrastructure series I’m talking about reducing the number of uplinks.

Wondering how exactly routing on hosts works? Dinesh Dutt explained the details in this 10-minute video during the Leaf-and-Spine Fabric Designs webinar.

I published the third installment of the Optimize Your Data Center Infrastructure story on my main web site. In this part I’m telling you to go with 10GE and consider 25GE.

I recently finished editing the videos from the Leaf-and-Spine Designs update to the Leaf-and-Spine Fabrics webinar, so it wasn’t hard to select the featured webinar for April 2017. The featured videos now include BGP in the Data Center by Dinesh Dutt, SPB Deep Dive by Roger Lapuh, and VXLAN with EVPN control plane by Lukas Krattiger.

Lukas Krattiger (Cisco Systems) was the guest speaker in Layer-2+3 fabrics part of the Leaf-and-Spine Fabric Design webinar, and he started his presentation with an overview of how we use overlays in data center fabrics.

During the Leaf-and-Spine Fabric Designs webinar Roger Lapuh from Avaya explained how Avaya uses SPB technology to build an L2+L3 fabric.

One of my readers watched my Leaf-and-Spine Fabric Architectures webinar and had a follow-up question:

You mentioned 3-tier architecture was dictated primarily by port count and throughput limits. I can understand that port density was a problem, but can you elaborate why the throughput is also a limitation? Do you mean that core switch like 6500 also not suitable to build a 2-tier network in term of throughput?

As always, the short answer is it depends, in this case on your access port count and bandwidth requirements.

One of my readers wondered what the difference between fabric extenders and leaf-and-spine fabrics is:

We are building a new data center for DR and we management is wanting me to put in recommendations to either stick with our current Cisco 7k to 2k ToR FEX solution, or prepare for what seems to be the future of DC in that spine leaf architecture.

Let’s start with “what is leaf-and-spine architecture?”