HandBook Series Virtual Extensible LAN VXLAN

فناوری VXLAN اجازه بخش‌بندی شبکه را می‌‌دهد درست به همان شکلی که شبکه محلی مجازی (VLAN) این‌کار را انجام می‌دهد، اما مزایای بیشتری نسبت به شبکه محلی مجازی در اختیار سرپرستان شبکه می‌گذارد. تکنولوژی VXLAN در راستای کمک به مجازی‌سازی معرفی شد. این تکنولوژی درست مثل VLAN می‌تواند شبکه‌ها را تقسیم‌بندی کند؛ بی‌آنکه محدودیت مقیاس VLAN را داشته باشد. حتی مزیت‌های بیشتری هم دارد. مثلا اینکه می‌توان ۱۶ میلیون VXLAN را در یک دامنه مدیریتی ایجاد کرد و تقسیم‌بندی‌هایی برای افزایش مقیاس شبکه و اجاره به کلاینت‌های بیشتر ایجاد کرد. در ادامه سه کتاب جهت آموزش VXLAN جهت دانلود قرار داده شده است.

Date: 2022
By: Toni Pasanen
Format: PDF
We are living in an era of Software Defined Networks (SDN) with Zero-touch installation, centralized Control Plane, Network Virtualization Overlay (NVO), Network Function Virtualization (NFV), and automated, self-learning networks where everything is managed as a system, not as individual components, via a graphical user interface. This is a huge benefit for business because everything that previously might take months can now be done in hours or even in minutes. However, it is often easy to forget that behind every SDN solution there is a highly complex system that consists of several physical/virtual devices and protocols which may fail. In these situations, it is crucial to understand how the system actually works, the role and the dependencies between protocols and so on. This book is an end-result of the author’s own journey to understand a system called VXLAN Fabric. This 370 pages book includes 19 chapters, 87 file captures, 135 figures, 342 examples (configuration, show commands, and ping/trace). Every example in this book is done by using a minimum amount of devices by using Cisco VIRL and EVE-NG. This way reader can make own verification and testing.

Chapters 1-7 explains the role and the operation of an Underlay Network discussing the Dijkstra algorithm used by OSPF and IS-IS as well as differences between them. It also introduces three BGP based solution (One-AS, Dual-AS, and Multi-AS). In addition, L2BUM forwarding based on “Anycast with PIM” and “PIM BiDir” solutions is explained. Chapters 8-10 explains the operation of the BGP L2VPN EVPN Control Plane. In addition, fabric external connection is discussed. Chapters 11-13 introduces vPC based multi-homing solution, while chapters 15-17 covers standard-based EVPN ESI Multi-Homing solution. Among these technologies, there are dedicated chapters for Firewall implementation, EVPN Multi-Site DC-Interconnect solution and Layer3 Multicast routing using Tenant Routed Multicast (TRM).

The intent of this book is to explain various design models for Overlay Network and Underlay Network used in VXLAN Fabric with BGP EVPN Control-Plane. The first two chapters are focusing on the Underlay Network solution. The OSPF is introduced first. Among other things, the book explains how OSPF flooding can be minimized with area design. After OSPF there is a chapter about BGP in the Underlay network. Both OSPF and BGP are covered deeply and things like convergence are discussed. After the Underlay Network part, the book focuses on BGP design. It explains the following models: (a) BGP Multi-AS with OSPF Underlay, this chapter discusses two design models – Shared Spine ASN and Unique Spien ASN, (b) BGP-Only Multi-ASN where both direct and loopback overlay BGP peering models are explained, (c) Single-ASN with OSPF Underlay, (d) Hybrid-ASN with OSPF Underlay – Pod-specific shared ASN connected via Super-Spine layer using eBGP peering, (e) Dual-ASN model where leafs share the same ASN and spines share their ASN. Each of the design model chapters includes a “Complexity Map” that should help readers to understand the complexity of each solution.

This book also explains BGP ECMP and related to ECMP, the book also covers ESI Multihoming. The last chapter introduces how two Pods, can also be geographically dispersed DCs, can be connected using Layer 3 only DCI with MPLS. I am using 5-stage Clos topology throughout the book. Some solutions are though explained by using only three switches for the sake of simplicity. I am also using IP-Only Underlay Network with Ingress-Replication, so this book does not cover Underlay Network Multicast solution. Besides, I am not covering DCI using Layer 2 Border Gateway (BGW) or Overlay Tenant Routing Multicast solution in this book because those, among the Underlay Multicast solutions, are covered in my first book “Virtual Extensible LAN – VXLAN: A Practical Guide to VXLAN solution” that is available at Amazon and Leanpub.I wanted to keep the focus of the book fairly narrow and concentrate on the Control-Plane design and functionality. Please be aware that this book does not give any recommendation to which solution is the best and which is not. It is the readers’ responsibility to find that out and selects the best solution for their needs. The book includes 66 images, 260 configuration/show command examples, and 32 packet captures.