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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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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Automate file uploads to your Cisco Nexus switches

If you have more than three Cisco Nexus switches in nx-os mode, and you are not using Cisco DCNM or any other similar tool, you probably already have encountered this question: How to automate file uploads to your Cisco Nexus switches? Here is a turnkey Python script using Netmiko’s SCP function to do this.

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Cisco NX-OS Graceful Insertion and Removal (GIR)

If you operate a data-center network with Cisco Nexus, you’ve probably already faced the problem of how to perform a maintenance on one of the two switches of a vPC pair, with minimum impact and risks for the production network. Cisco NX-OS contains a feature called “Graceful Insertion and Removal” or GIR to help you for that. Here is how it works.

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