Network Programmability with YANG: The Structure of Network Automation with YANG, NETCONF, RESTCONF, and gNMI

Cisco has gone all-in on model-driven management across all major operating systems. Modern versions of IOS-XE, IOS-XR, and NX-OS all support YANG-powered NETCONF with IOS-XE and NX-OS also supporting RESTCONF and IOS-XR supporting gNMI. Moreover, in addition to pushing configuration changes and pulling config and operational state via model-driven protocols, these same platforms support streaming telemetry based on the same YANG data models. The promises of model-driven management with model-driven telemetry include more reliable and scalable configuration changes, real-time collection of operational data, and a true programmatic interface without the need to do any screen-scraping.

So how do you, as a customer, get started with this model-driven paradigm to network programmability? How do you determine the right YANG modules to use to perform your configuration tasks and collect your network telemetry? How do you learn the nuances of the various YANG-powered protocols? If you’re an operator who is designing service-level modules to be consumed by you or your customers how do you learn how to create, test, and deploy structurally valid and elegant YANG data models?

“Network Programmability with YANG” is the definitive reference to help you navigate the sea of model-driven management and automation. It introduces YANG as a data modeling languags, describes the protocols based on it, and explores the advantages one gets by embracing this paradigm. The 460 pages book goes on to describe the syntax of YANG modules and how to write clean, descriptive, and well-performing modules of your own. Attention is paid to helping you find the right YANG modules to solve your problems, as well as showing you tools to make using them in your own applications much easier. Finally, each chapter concludes with an interview of industry experts and operators that have already started to walk down the path of model-drive management to give you words of wisdom and expert perspectives to make your journey as successful as possible.

Description

Today, networks must evolve and scale faster than ever. You can’t manage everything by hand anymore: You need to automate relentlessly. YANG, along with the NETCONF, RESTCONF, or gRPC/gNMI protocols, is the most practical solution, but most implementers have had to learn by trial and error. Now, Network Programmability with YANG gives you complete and reliable guidance for unlocking the full power of network automation using model-driven APIs and protocols. Authored by three YANG pioneers, this plain-spoken book guides you through successfully applying software practices based on YANG data models. The authors focus on the network operations layer operations, emphasizing model-driven APIs, and underlying transports. Whether you’re a network operator, DevOps engineer, software developer, orchestration engineer, NMS/OSS architect, service engineer, or manager, this guide can help you dramatically improve value, agility, and manageability throughout your network.

• Discover the value of implementing YANG and Data Model-Driven Management in your network
• Explore the layers and components of a complete working solution
• Build a business case where value increases as your solution grows
• Drill down into transport protocols: NETCONF, RESTCONF, and gNMI/gRPC
• See how telemetry can establish a valuable automated feedback loop
• Find data models you can build on, and evaluate models with similar functionality
• Understand models, metadata, and tools from several viewpoints: architect, operator, module author, and application developer
• Walk through a complete automation journey: business case, service model, service implementation, device integration, and operation
• Leverage the authors’ experience to design successful YANG models and avoid pitfalls

Reference: http://www.informit.com/store/network-programmability-with-yang-the-structure-of-9780135180396

Table of Contents

Introduction xxii
1 The Network Management World Must Change: Why Should You Care?
   Introduction
   The Industry Has Changed: What Are the Trends?
   Existing Network Management Practices and Related Limitations
   Data Modeling Is Key for Automation
   Interview with the Experts
   Summary
   References in This Chapter
   Endnotes
2 Data Model—Driven Management
   The Beginning: A New Set of Requirements
   Network Management Is Dead, Long Live Network Management
   YANG: The Data Modeling Language
   The Management Architecture
   Data Model—Driven Management Components
   The Encoding (Protocol Binding and Serialization)
   The Server Architecture: Datastore
   The Protocols
   The Programming Language
   Telemetry
   The Bigger Picture: Using NETCONF to Manage a Network
   Interview with the Experts
   Summary
   References in This Chapter
   Endnotes
3 YANG Explained
   Introduction
   Describe Your World of Data
   Describing Possible Events
   Separating Configuration from Operational Data
   Constraints Keep Things Meaningful
   Augmenting, Extending, and Possibly Deviating
   Network Management Datastore Architecture (NMDA)
   Interview with the Expert
   Summary
   References in This Chapter
4 NETCONF, RESTCONF, and gNMI Explained
   Introduction
   NETCONF
   RESTCONF
   OpenConfig and gNMI
   Interview with the Expert
   Summary
   References in This Chapter
5 Telemetry Explained
   Introduction
   Data Model—Driven Telemetry
   Moving Away from SNMP to Telemetry
   Telemetry Use Cases
   Telemetry Components
   Telemetry Standard Mechanisms
   Interview with the Experts
   Summary
   References in This Chapter
   Endnotes
6 YANG Data Modeling Developments in the Industry
   Introduction
   The Beginning: The IETF
   Embracing YANG Throughout the Industry
   The OpenConfig YANG Model
   Industry Coordination Is Required
   Interoperability Testing
   Implementing More Than One YANG Model for a Specific Functionality
   Interview with the Expert
   Summary
   References in This Chapter
   Endnotes
7 Automation Is as Good as the Data Models, Their Related
   Metadata, and the Tools: For the Network Architect and Operator
   Introduction
   Getting to Know the Structure of a YANG Module
   Finding the Right Modules Using the YANG Catalog
   Interacting with Devices
   Interview with the Experts
   Summary
   Endnotes
8 Automation Is as Good as the Data Models,
   Their Related Metadata, and the Tools: For the Module Author
   Introduction
   Designing Modules
   Understanding Your Module’s Impact
   Interview with the Expert
   Summary
   Endnotes
9 Automation Is as Good as the Data Models, Their Related Metadata, and the Tools: For the Application Developer
   Introduction
   Working with YANG Modules
   Interacting with the Network
   Making YANG Language Native
   Interview with the Expert
   Summary
   Endnotes
10 Using NETCONF and YANG
   Introduction
   So the Story Goes
   Top-Down Service Model
   Bottom-Up Device Templates
   Service Logic Connecting the Dots
   Setting Up NETCONF on a Device
   Discovering What’s on a Device
   Managing Services
   Manager Synchronization with Devices
   Network-Wide Transactions
   Interview with the Experts
   Summary
11 YANG Model Design
   Introduction
   Modeling Strategy
   YANG Modeling Tips
   Common YANG Mistakes
   Backward Compatibility
   Interview with the Experts
   Summary
   References in This Chapter