Understanding and Troubleshooting Cisco Catalyst 9800 Series Wireless Controllers

Simone Arena is a principal technical marketing engineer (TME) within the Cisco Enterprise Networking & Cloud group and is primarily focused on enterprise network architecture and on all things related to wireless and mobility. Simone is based in Italy and is a Cisco veteran, having joined Cisco in 1999. Throughout the years, Simone has covered multiple roles at Cisco, starting as a software engineer working with Catalyst switching platforms, to consulting system engineer in the field, to TME within different teams (Enterprise Solution Engineering, Wireless Business Unit, Enterprise Networking and Cloud, and now Networking Experiences Group). Today Simone is the lead TME architect for Catalyst Wireless, and his time is split between helping customers and partners design the best solution that fits their needs and engineering and product management, trying to evolve and improve the products and solutions. Simone is a Distinguished Speaker at Cisco Live and has spoken at Cisco Live events all over the world for several years. Besides wireless and networking, Simone has two passions: his family, with his two daughters Viola and Anita; and Fiorentina, the best soccer team in the world...no question. In his spare time, Simone enjoys listening to music, especially through his new tube amplifier (simply awesome!).Francisco Sedano Crippa, CCIE No. 14859, joined Cisco in 2006. After some years at TAC supporting voice solutions and as a system engineer working with service providers, he moved to the development side, where he worked on routing, datacenter and, during the past 10 years, as a technical leader on the Wireless Controller development team, focused in serviceability, location services, programmability, and cloud. He’s a Cisco Live speaker and is passionate about DevOps and automation, and he is now working on architecting next-generation cloud-based lab services. When not working, he spends his time building a full-size Boeing 737 simulator in his basement and enjoying his other passion: his daughter, Scarlett, and son, Marco, and his wife, Isabel.Nicolas Darchis, CCIE Wireless No. 25344, joined the Wireless and AAA Cisco TAC team in Belgium in 2007, where his main focus was troubleshooting wireless networks, wireless management tools, and security products. Since 2016, Nicolas has been working as a technical leader for wireless at the same technical assistance center in Brussels; he has shifted a big part of his focus to improving product serviceability of new and upcoming products, as well as new software releases. He is also a major contributor to online documentation of Cisco wireless products and has participated in many of the wireless “Ask the Expert” sessions run by the Cisco support community. Nicolas has been a CCIE Wireless No. 25344 since 2009 and, more recently, he has achieved CWNE No. 208.Sudha Katgeri, CCIE No. 45857, is a technical leader in services for Enterprise Wireless and has been with Cisco since 2006. Besides supporting customer escalations, Sudha collaborates with Customer Experience (CX), Enterprise Networking (ENB) Escalation, Engineering, and Product Management to improve product quality and serviceability in the next-generation Catalyst wireless stack. Sudha has a CCIE in Wireless (#45857) and is an author and contributor to Wireless TAC Innovation Tools like Wireless Config Converter, CLI Analyzer, and several documents on cisco.com.

• Introduction xxviiChapter 1 Cisco C9800 Series 1Why Cisco C9800? 2The Role of the Wireless Controller in a Cloud Era 7Managing the Cisco C9800 10Cisco Next-Generation Wireless Stack 22Summary 23References 23Chapter 2 Hardware and Software Architecture of the C9800 25General CAPWAP Split MAC Architecture 25The Controller Control Plane Architecture Elasticity 27Wireless Client State Machine 31One Dataplane to Rule Them All (or Three at the Maximum) 35Hardware Overview 38Summary 42Chapter 3 C9800 Configuration Model 43C9800 New Configuration Model 43Cisco C9800 Series Profile and Tag Considerations 48Summary 64References 64Chapter 4 C9800 Deployment and Installation 65C9800 Deployment Models 65Setting Up Your First Catalyst Wireless Network 79Summary 87References 87Chapter 5 Security 89Network Security Fundamentals 89Wireless Security Fundamentals 116Securing the Air 128Securing Your Access Points 148Securing Your Wireless Controller 151Encrypted Traffic Analytics 154Cisco Umbrella 155Cisco Secure Development Lifecycle (CSDL) 157Summary 157References 157Chapter 6 Mobility and Client Roaming 159802.11 Roaming 160Types of Client Roaming 181C9800 to AireOS Inter-Release Controller Mobility (IRCM) 191Summary 192References 193Chapter 7 RF Deployment and Guidelines 195Radio Resources Management (RRM) Concepts and Components 195Challenging RF Environments 199Radio Resources Management (RRM) 203DCA 211RF Profiles 215Spectrum Intelligence and CleanAir 219Advanced RF Features 224Airtime Fairness (ATF) 228Dynamic Frequency Selection (DFS) 232Flexible Radio Assignment (FRA) 235Wireless Intrusion Prevention System (WIPS) and Rogue Detection 238Summary 246References 246Chapter 8 Multicast and Multicast Domain Name System (mDNS) 247Wireless Multicast 250Media Stream Feature 263mDNS 272Summary 283References 283Chapter 9 Quality of Service (QoS) 285Wi-Fi Quality of Service (QoS) 286Wi-Fi (802.11) QoS Fundamentals 287Implementing Wireless QoS on the C9800 300Designing and Deploying Catalyst C9800 QoS 304Best Practices 320Summary 322References 322Chapter 10 C9800 High Availability 323SSO Redundancy 324HA Teardown 349SSO Deployment: Impact on Features 350N+1 Redundancy 352N+1 vs. SSO High Availability 357HA in EWC-AP Deployment 358HA in EWC-SW Deployment 359Summary 359References 360Chapter 11 Cisco DNA Spaces Integration and IoT 361Value-Added Wireless Services 361Connected Mobile Experiences (CMX) 372Cisco DNA Spaces 372Specific Service Examples 379Summary 392References 392Chapter 12 Network Programmability 393What Is Network Programmability? 393Why Is Network Programmability Needed? 393Is Network Programmability a New Concept? 396Orchestration of the Entire Network 396Configuration Repeatability 396Idempotency 397Imperative vs. Declarative Models 397Infrastructure as Code (IaC) 400Network Programmability in the C9800 401Data Models 402YANG Data Models 403Encoding Formats 406Protocols 408Tools to Examine YANG Models 412How to Examine Data Using NETCONF and YANG Suite 419How to Examine Data Using RESTCONF and POSTMAN 421Python and Network Programmability 429Summary 436References 436Chapter 13 Model-Driven Telemetry 437What Is Model-Driven Telemetry? 437How to Enable Model-Driven Telemetry 438Operational Data and KPIs 441Polling vs. Subscribing 447Telemetry Streams 448How to Identify Subtrees in YANG Models 449Dial-out vs. Dial-in 450Tools 460Summary 467References 467Chapter 14 Cisco DNA Center/Assurance Integration 469Introduction 469Managing the C9800 with Cisco DNA Center 472Summary 492References 492Chapter 15 Backing Up, Restoring, and Upgrading Your C9800 493Saving and Restoring the Configuration for Disaster Recovery 493Running IOS-XE in Install or Bundle Mode 500Upgrading (and Downgrading) the Controller Safely 501Summary 506References 506Chapter 16 Troubleshooting 507Control Plane Tracing 509Embedded Packet Capture (EPC) 525Packet Tracer 531Troubleshooting Dashboard 536Other On-the-Box Tools on the C9800 GUI 540Offline Tools for the C9800 545Health and KPI Monitoring 548Summary 577References 578Appendix A Setting Up a Development Environment 5799780137492329, TOC, 5/27/2022