Ever wonder what it would be like to have a platform dedicated to Continuous Improvement / Testing / Labbing? Cisco's put a lot of thought into good ways to do that, and Cisco Modeling Labs(CML) is the latest iteration of their solutions to provide this as a service to enterprises and casual users alike. CML is the …

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VMware's NSX Datacenter product is designed for a bit more than single enterprise virtual networking and security. When reviewing platform maximums (NSX-T 3.2 ConfigMax), the listed maximum number of Tier-1 routers is 4,000 logical routers. Achieving that number takes a degree of intentional design, however. When …

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What is the point of all this software-defined infrastructure if you don't use it? In prior examples, it's a fairly straightforward path to SDN when deploying NSX Data Center, allowing a VI admin or network engineer to deploy virtual network resources via a GUI. This isn't the end of an effort, but the start of a …

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Idempotence and Declarative Methods - not just buzzwords Idempotence Coined by Benjamin Peirce, this term indicates that a mathematical operation will produce a consistent result, even with repetition. Idempotence is much more complicated subject in mathematics and computer science. IT and DevOps use a simplified …

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Note: This feature has been deprecated by VMware NSX-T 3.2 has been released, and has a ton of spiffy features. The NSX ALB integration is particularly neat, but while repeatedly (repeatably) breaking the integration to learn more about it, I ran into this error: When deploying NSX ALB appliances from the NSX Manager, …

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DNS is a vital component of all computer networks. Also known as the "Internet Yellow Pages," this service is consumed by every household. DNS services are typically deployed in several patterns to support users and systems: DNS Forwarder: This deployment method is the most common. Everybody needs name …

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At some point, we can't "do it all" with one block of code. As developers, we need to store persistent data for a variety of reasons: We want it for later execution (or to compare it to another result) We're sick of storing variables in code. This matters a lot more in compiled languages than runtime ones We …

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It's probably safe to say that service provider networking is pretty unique. One particular design pattern - Looking Glasses - is extremely useful for complex dynamically routed networks. I'd really like to shift the gatekeeping needle here - networks that are complex enough to benefit from a looking glass should move …

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NGINX Rewrite Directives, The 9/10 Solutions When doing ADC/Load Balancer work, nearly all requests fit into two categories: Please rewrite part of the URL/URI Please change the host header for this reverse proxy These are fairly simple to implement in NGINX, so I'm creating a couple of cheat-sheet code snippets here. …

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Don't Reinvent the Wheel: Ansible Playbooks Writing your own code isn't always the answer Often, communities such as Python will contribute code of substantially higher quality than what you/I can create individually. This is OK. In nearly every case, dyed-in-the-wool traditionalist programmers will consume …

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