Niki Vonderwell kindly invited me to Troopers 2017 and I decided to talk about security and reliability aspects of network automation.

The presentation is available on my web site, and I’ll post the link to the video when they upload it. An extended version of the presentation will eventually become part of Network Automation Use Cases webinar.

The last presentation during the Tech Field Day Extra @ Cisco Live Europe event was a Cisco-Apple Partnership presentation, and we expected an hour of corporate marketese.

Can’t tell you how pleasantly surprised we were when Jerome Henry started his very technical presentation explaining the wireless goodies you get when using iOS with IOS.

Just FYI: a week after I wrote this (don't forget to go through the comments), VMware made it official:

…we’ve found that VMware’s native virtual switch implementation has become the de facto standard for greater than 99% of vSphere customers today. … Moving forward, VMware will have a single virtual switch strategy that focuses on two sets of native virtual switch offerings – VMware vSphere® Standard Switch and vSphere Distributed Switch™ for VMware vSphere, and the Open virtual switch (OVS).

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

Ansible network modules (at least in the way they’re implemented in Ansible releases 2.1 and 2.2) were one of the more confusing aspects of my Building Network Automation Solutions online course (and based on what I’m seeing on various chat sites we weren’t the only ones).

I wrote an in-depth explanation of how you’re supposed to be using them a while ago and now updated it with user authentication information.

One of the engineers watching my Data Center 3.0 webinar asked me why we need session stickiness in load balancing, what its impact is on load balancer performance, and whether we could get rid of it. Here’s the whole story from the networking perspective.

Remember the All You Need Are Two Switches saga? Several readers told me they’d like to have in text (article) format, so I found a transcription service, and started editing what they produced and publishing it. The first two installments are already online.

On a related topic: we’ll discuss the viability of this approach in April DIGS event in Zurich, Switzerland.

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.

In autumn 2016 I embarked on a quest to figure out how TCP really works and whether big buffers in data center switches make sense. One of the obvious stops on this journey was a chat with Thomas Graf, Linux Core Team member and a founding member of the Cilium project.

When Cisco ACI was launched it promised to do everything you need (plus much more, and in multi-hypervisor environment). It was quickly obvious that you can’t do all that on ToR switches, and need control of the virtual switch (the real network edge) to get the job done.