VXLAN Journey - Part 01 - What is VXLAN and how it works (Cisco Nexus Switch) - Basic data plane learning
For several years I have worked with Data-Center network based on VXLAN. Anyone suddenly start working with production DC-networks built on top VXLAN - with Spine-Leaf topology and Multi-Site - they will get lost easily. Also lack of good step by step written books from the vendors Cisco, Arista, Juniper etc. make it difficult to understand the technologies/protocols used for VXLAN in DC-network. Let's try to solve the problem - by building a DC-network from scratch and step by step using Cisco Nexus switches. What is VXLAN? The most common answer is - tunnelling a layer-2 packets over layer-3 network. I define it another way - the whole DC is a fabric. A fabric consists of several switches. With VXLAN, the whole DC-Fabric becomes a single switch (of course - logically). We are eliminating three fundamental problems in DC - The network core becomes Spanning Tree Protocol (STP) free. All the physical links in the core are used Equal-cost multi-path routing (ECMP). The network...