README

ExaBGP Documentation Research - Claude Resources

Created: 2025-11-09 Purpose: Comprehensive knowledge base for ExaBGP documentation writers Status: Complete

Overview

This directory contains comprehensive research and knowledge gathered from external resources about ExaBGP use cases, architecture, and implementation patterns. This information serves as the foundation for writing the ExaBGP wiki documentation.

Directory Structure

.claude/
├── README.md                           # This file - index of all resources
├── use-cases-summary.md                # Main summary of all ExaBGP use cases
├── architecture-overview.md            # Technical architecture reference
└── resources/                          # Detailed topic-specific documentation
    ├── api-reference.md                # Complete API documentation
    ├── flowspec-ddos-mitigation.md     # FlowSpec and DDoS use cases
    ├── health-checks-implementation.md # Health check patterns and code
    ├── high-availability-patterns.md   # HA architecture and examples
    ├── vincent-bernat-articles.md      # Vincent Bernat's ExaBGP articles
    ├── facebook-katran.md              # Facebook/Meta Katran L4LB (hyperscale)
    ├── user-stories-presentations.md   # 47+ user stories, blogs, presentations
    └── bgp-implementations-comparison.md # 26+ BGP implementations compared

Main Documents

1. use-cases-summary.md ⭐ START HERE

Comprehensive overview of all ExaBGP use cases:

• DDoS Mitigation via FlowSpec
• Anycast High Availability
• Dynamic Load Balancing
• Traffic Engineering and SDN Integration
• Network Automation and Route Injection
• Network Blacklisting and Security
• Cloud and Virtual Infrastructure
• Protocol and Scale Testing

Also includes:

• Integration patterns
• Industry adoption and real-world examples
• Comparison with alternatives
• Best practices and common pitfalls
• Performance characteristics
• Links to all 98 configuration examples

Use this for: Understanding what ExaBGP can do, writing use case documentation, creating examples.

2. architecture-overview.md

Technical deep-dive into ExaBGP's internal architecture:

• Component architecture (Process Manager, Parser, BGP State Machine, etc.)
• Data flow diagrams
• Protocol implementation details (55+ RFCs)
• Address family support
• Threading model
• Security architecture
• Deployment patterns

Use this for: Understanding how ExaBGP works internally, explaining technical concepts, advanced documentation.

Resource Files (./resources/)

3. resources/api-reference.md

Complete API documentation:

• API architecture (STDIN/STDOUT)
• Command reference (announce, withdraw, control commands)
• JSON vs. Text encoders
• Python integration examples
• Route attributes reference
• Error handling and debugging

Use this for: API documentation, command reference, integration guides.

4. resources/flowspec-ddos-mitigation.md

FlowSpec and DDoS mitigation:

• What is FlowSpec and how it works
• Use cases (automated DDoS response, ML integration, upstream mitigation)
• Configuration patterns
• Real-world implementations (Arbor, Cisco IOS-XR)
• Match conditions and actions
• Best practices
• Example scenarios

Use this for: FlowSpec documentation, DDoS mitigation guides, security use cases.

5. resources/health-checks-implementation.md

Health check implementation patterns:

• Built-in ExaBGP healthcheck module
• Custom health check scripts (TCP, HTTP, database, Redis)
• Advanced patterns (retry logic, dampening, load-based metrics)
• Third-party tools (ExaCheck, community scripts)
• Maintenance mode implementation
• Monitoring and logging

Use this for: Health check documentation, HA guides, operations documentation.

6. resources/high-availability-patterns.md

High availability architecture:

• Architecture patterns (direct announcement, route servers)
• Service IP allocation strategies
• Metric-based load distribution
• Health check implementation
• Use case examples (anycast DNS, web services, database replicas, CDN)
• Integration with load balancers (HAProxy, NGINX)
• Maintenance and troubleshooting

Use this for: HA documentation, anycast guides, load balancing documentation.

7. resources/vincent-bernat-articles.md

Vincent Bernat's ExaBGP and BGP articles:

• High availability with ExaBGP (2013)
• Multi-tier load balancing with Linux (2018)
• L3 routing to hypervisor with BGP
• BGP LLGR, RPKI, and other BGP topics
• Production-tested architectures
• Integration patterns (ECMP, IPVS, HAProxy)
• File-based health check control
• Feature gap analysis (LLGR, RPKI, BFD support)

Use this for: Production deployment patterns, multi-tier architectures, integration examples, expert-validated approaches.

8. resources/facebook-katran.md ⭐ HYPERSCALE VALIDATION

Facebook/Meta's Katran L4 Load Balancer using ExaBGP:

• ExaBGP at hyperscale (billions of users)
• Why Facebook chose ExaBGP: "lightweight, flexible design"
• ExaBGP + ECMP + DSR architecture
• Production-tested for years
• Open source reference implementation
• Health check integration patterns
• Stateless horizontal scaling
• Mission-critical deployment

Use this for: Proving ExaBGP works at scale, L4 load balancing use case, ECMP patterns, reference architecture, "who uses ExaBGP" section.

9. resources/user-stories-presentations.md ⭐ 47+ SOURCES

Comprehensive catalog of ExaBGP users, blogs, and presentations:

• 47+ documented sources (2010-2025)
• Production deployments (Facebook, Charter, ISPs)
• Technical blogs (Vincent Bernat, ThePacketGeek, Das Blinken Lichten, etc.)
• Conference presentations (LINX, NANOG, RIPE, FRnOG)
• DNS anycast implementations
• DDoS mitigation case studies (FastNetMon, ElastiFlow)
• Kubernetes/cloud integrations
• Tools and integrations
• 2025 content included

Use this for: Finding user stories, linking to tutorials, proving community support, citing real deployments, showing diversity of use cases, "who uses ExaBGP" documentation.

10. resources/bgp-implementations-comparison.md ⭐ 26+ BGP IMPLEMENTATIONS

Comprehensive comparison of all open source BGP implementations:

• 26+ implementations documented (C, Python, Go, Rust, Java, Ruby, Erlang, Haskell)
• Performance benchmarks (BIRD fastest, GoBGP slowest)
• Memory usage comparisons
• Feature matrices and use case recommendations
• Production-ready vs experimental status
• Major players: BIRD, FRRouting, ExaBGP, GoBGP, OpenBGPD
• Emerging: RustyBGP, bio-routing, CoreBGP
• Specialized: freeRouter (Java), YABGP (analysis), pmacct (monitoring)
• Historical evolution (GNU Zebra → Quagga → FRRouting)
• Decision matrix by use case

Use this for: Comparing ExaBGP with alternatives, showing ExaBGP's pioneer position (first OSS FlowSpec, now also in GoBGP/FRR/BIRD), recommending tools for specific needs, ecosystem awareness.

Key Findings Summary

ExaBGP's Unique Value Propositions

1. Pioneered Open-Source FlowSpec (First Implementation)

   • Full RFC 5575/8955 support
   • Most API-friendly FlowSpec implementation
   • Easy integration with DDoS detection systems
   • Now also supported by: GoBGP, FRRouting, BIRD

2. Pure BGP Protocol Implementation

   • No RIB/FIB manipulation
   • 55+ RFCs implemented
   • Protocol correctness focus

3. Simple API Design

   • STDIN/STDOUT communication
   • Language-agnostic
   • Easy integration with any tool

4. Proven at Scale

   • Thousands of deployments
   • Companies: Shutterstock, LinkedIn, NSONE
   • 98 configuration examples

Primary Use Cases (Priority Order)

1. DDoS Mitigation - Most compelling use case, unique capability
2. Anycast HA - High availability for critical services
3. Load Balancing - Dynamic traffic distribution
4. Traffic Engineering - SDN integration, path optimization
5. Network Automation - Application-driven routing

Documentation Priorities

Based on research, focus documentation on:

Tier 1 (Critical - Write First):

• Quick Start Guide with anycast example
• API Overview and Reference
• FlowSpec Overview and DDoS Mitigation
• Health Checks Guide
• High Availability Guide

Tier 2 (Important - Write Second):

• Load Balancing Use Cases
• Traffic Engineering
• Configuration Syntax
• Operations Guide

Tier 3 (Enhancement - Write Last):

• Advanced Features
• Cloud Integration
• Protocol Details
• Performance Tuning

External Resources Referenced

Key Articles (Cached Knowledge)

• ✅ Vincent Bernat - "High Availability with ExaBGP"
• ✅ RIPE Labs - "ExaBGP: From Route Injector to BGP Engine"
• ✅ thepacketgeek.com - Getting Started Guide
• ✅ thepacketgeek.com - Automating ExaBGP
• ✅ Multiple conference presentations (RIPE, UKNOF, LINX, UKUUG, SWINOG)

Community Resources

• ✅ sysadminblog/exabgp-healthcheck (Perl-based health checker)
• ✅ ExaCheck - Dedicated BGP health checker
• ✅ GitHub examples and community scripts

Commercial Integrations

• ✅ Arbor SP/TMS - DDoS detection with FlowSpec
• ✅ Wanguard - BGP Connector for FlowSpec
• ✅ ElastiFlow - Flow analysis with ML

How to Use These Resources

For Documentation Writers

1. Start with use-cases-summary.md

   • Understand all use cases
   • Identify which documentation to write
   • Reference real-world examples

2. Reference topic-specific files in resources/

   • Copy code examples
   • Use architecture patterns
   • Understand implementation details

3. Use architecture-overview.md for technical depth

   • Explain how things work
   • Justify design decisions
   • Advanced topics

4. Cross-reference between documents

   • Link related topics
   • Provide complete user journey
   • Avoid duplication

For New AI Sessions

When resuming documentation work:

1. Read .claude/README.md (this file)
2. Read CLAUDE.md for progress tracking
3. Read DOCUMENTATION-PLAN.md for overall structure
4. Reference topic-specific files in .claude/resources/ as needed
5. Continue with next pending task from CLAUDE.md

Statistics

Total External Resources Fetched: 9 web searches + 4 detailed web fetches Total Documentation Created: 6 files Total Content: ~50,000 words Topics Covered: 8 major use cases + architecture + API + health checks + HA patterns + FlowSpec Code Examples: 50+ Python/config examples Real-World References: 20+ companies and projects

Key Messages for Documentation

These messages must be reinforced throughout all documentation:

1. ✅ ExaBGP does NOT manipulate RIB/FIB
2. ✅ ExaBGP is a pure BGP protocol implementation
3. ✅ External processes handle routing decisions via API
4. ✅ Only open-source FlowSpec implementation
5. ✅ 55+ RFCs implemented at protocol level
6. ✅ Simple STDIN/STDOUT API for any language
7. ✅ 98 configuration examples available
8. ✅ Proven at scale (thousands of deployments)

Next Steps

With this research complete, proceed to:

1. ✅ Update /main/README.md with documentation section
2. 📝 Create Phase 2 Tier 1 Critical Documentation:
   • Quick-Start.md
   • Installation-Guide.md
   • First-BGP-Session.md
   • API-Overview.md
   • Text-API-Reference.md
   • JSON-API-Reference.md
   • FlowSpec-Overview.md
   • And more...

See CLAUDE.md for detailed progress tracking.

Maintenance

When to Update:

• New ExaBGP features released
• New use cases discovered
• Community contributions
• RFC updates

How to Update:

1. Add new findings to appropriate .md file
2. Update this README.md with summary
3. Update CLAUDE.md progress tracker
4. Regenerate affected wiki documentation

Questions?

For documentation questions, consult:

1. These .claude/ files first (comprehensive)
2. DOCUMENTATION-PLAN.md (structure and phasing)
3. CLAUDE.md (progress and decisions)
4. RFC-SUPPORT.md (RFC compliance)
5. Official ExaBGP GitHub wiki (reference)

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Documentation Quality Checklist (apply to all wiki docs):

• Emphasizes no RIB/FIB manipulation
• Includes practical example from etc/exabgp/ configs
• Cross-references related documentation
• Has "See Also" section
• Contains working code examples
• Lists common errors and solutions
• Links to relevant RFCs where applicable
• Explains BGP protocol behavior
• Suitable for target audience (beginner/intermediate/advanced)
• Uses consistent terminology and style

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Created by Claude (Sonnet 4.5) - 2025-11-09