Before getting started, let's cover what different IP message types exist in a brief summary, coupled with a "day in the life of a datagram" as it were. Unicast: One source, one well-defined destination. Most network traffic falls into this category. Mayfly perspective: Source device originates packet, and …

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Since most of NSX-T runs in a firewall mode of sorts, it's probably worthwhile to discuss on of the less well-known routing protocol features - Graceful Restart. As published for BGP, IETF RFC 4724 outlines a mechanism for "preserving forwarding traffic during a BGP restart." This definition may be a little …

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Now that the primary infrastructure components for NSX-T are in place, it is now possible to build-out the actual functions that NSX-T is designed to provide. A friendly suggestion, make sure your Fabric is healthy before doing this: NSX-T differs from NSX-V quite a bit here. Irregular topologies between edge routers …

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Since NSX-T 2.5 just came out, it's about time to do a full rebuild and getting started guide. NSX-T differs greatly from NSX-V in that the initial setup is quite a bit more complicated and doesn't have many guardrails or direct paths to initial set-up. We'll be skipping the appliance deployment, because if you have …

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With the previous post, I covered traditional data center networking, and some of the reliability compromises made to accommodate typical workloads. Here I'll be outlining my take as a series of blog posts on the next iteration of data center network design, Spine and Leaf: Lab Diagram What came before Introduction: …

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So far, this is all great, but it IS missing something Networks are useless unless you do something with it. In most cases, a device (in this case, we'll use a server) needs to connect via redundant links to a common Layer 2 segment. Why is this? Well, most servers are incapable of dynamic routing. Instead, the server …

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So far, all examples to date have been extremely simple, and stand rather well on their own (OSPF Clos would work just FINE in a campus network if you have cheap L3) but may not effectively address some more advanced use cases. In short, we're about to enter niche territory. Generally speaking, BGP is regarded as the …

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Overview First off, here's the reference diagram (YAML): Assumptions about difficulty Most people I've met outside of the carrier space are pretty intimidated by BGP, as it is truly impressive in scope. Here, we're going to break-out BGP usage into two categories: iBGP: This is where all nodes have the same Autonomous …

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As covered in the previous post, base configuration of a spine-and-leaf fabric is actually pretty simple. This will be pretty short, but we'll cover the conversion of the previously built fabric to OSPF. Here's the updated diagram: (YAML). As we move to a more full-fledged implementation, we'll do dual-stack. The …

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This is only slightly trolling, but is primarily to outline the topological simplicity of Spine-and-Leaf networking, in a way that is suspiciously similar to Cisco classes. First things first, here's the diagram. This is performed using a set of four Cat3560s, enterprise licensed and wired in a redundant square …

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