The Future of Network Engineering in the AI/ML era

It seems like yesterday when I saw my first network automation presentation at a conference. I remember it very well; it was in 2015 at the Cisco Network Innovation Summit in Prague. Mr. Tim Szigeti was presenting the first version of the Cisco APIC-EM, the future Cisco Digital Network Architecture (DNA) controller. I talked already about it in a previous article, written in 2018, about my journey toward network programmability and automation. After its presentation, and for many years afterward, the question was on everyone’s lips:

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Migrating Cisco FabricPath and Classic Ethernet Environments to VXLAN BGP/EVPN over a 400Gb-based Clos Topology, part 1 – the why

During the past three years, I have spent a good portion of my time testing, planning, designing, and then migrating our DC network from Cisco FabricPath and Classic Ethernet environments to VXLAN BGP/EVPN. And simultaneously, from a hierarchical classic two-tier architecture to a more modern Clos 400Gb-based topology. The migration is not yet 100% completed, but it is well underway. And I have gained significant experience on the subject, so I think it’s time to share my knowledge and experiments with our community.

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Cisco DCAUTO exam study resources

I just passed the Cisco DevNet DCAUTO (300-635) exam (Yay!). This is my 3rd Cisco exam on network automation after NPDESI in 2018 (replaced now by the DevNet program), and DevNet CORE (DEVCOR) in 2020. But this time, I documented everything I read, so I could report it here and build a Cisco DCAUTO exam study resources. By doing this, I hope to help anyone who wants to study for this certification. And, as I have already passed the DevNet CORE exam, I am now Cisco certified DevNet Professional.

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First steps with pyATS

Have you ever wanted to compare the operational state of a bunch of network devices between two specific times? Not only if the interfaces are up or down, but the number and status of BGP peers, the number of prefixes received, the number of entries into a MAC-address table, etc? This is something quite laborious to do with classical NMS or Do-It-Yourself scripts. And this is where pyATS can become a real asset. Here are my first steps with pyATS: Network Test & Automation Solution.

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How to simulate a host in a real network?

Like some other posts, I didn’t think I would write this one because it seemed obvious. But, after talking to a lot of engineers and customers, I realized that not everyone knows this trick. So here it is. The question is this: how to simulate a real host in a physical network environment when you don’t have computer at your disposal? Well, let’s take an example.

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