BGP Configuration Analysis & Troubleshooting
Analyze and troubleshoot BGP configurations and routing issues
What You Can Do
You can validate BGP configurations, diagnose routing problems, and optimize network convergence. This skill analyzes your router configurations, show command outputs, and topology details to identify misconfigurations, security gaps, and performance bottlenecks—then provides step-by-step fixes and best practices for your specific setup.
Features
Detect syntax errors, missing parameters, and configuration inconsistencies across Cisco, Juniper, and Arista platforms
Analyze neighbor states, timers, and capability mismatches causing adjacency failures
Trace why routes aren't being advertised or received; validate route filtering and policy logic
Evaluate AS path manipulation strategies and identify suboptimal route selection
Identify causes of slow convergence and recommend timer adjustments and failover strategies
Detect route hijacking risks, missing prefix filters, and unauthorized AS path injection vulnerabilities
Analyze iBGP, eBGP, and route reflector designs across complex topologies
Generate actionable fix steps with before/after config examples and validation checklists
Example Output
Input: BGP neighbor stuck in Active state
Output:
- Root cause: Outbound route filter blocking 192.168.1.0/24
- Evidence: Neighbor config missing route-map on export
- Fix steps:
- Add
route-map EXPORT-TO-NEIGHBOR outto neighbor config - Permit 192.168.1.0/24 in the route-map
- Reload BGP session
- Add
- Verify:
show bgp neighbors X.X.X.X advertised-routesshould list your prefixes
Input: Routes not reaching spoke sites
Output:
- Hub config issue: Route reflector not configured with
cluster-id - Spoke issue: iBGP neighbors missing
update-source - Fix: Enable route reflector on hub, update spoke iBGP peers, validate with
show bgp ipv4 unicast summary
What's Included
- SKILL.md: Core BGP analysis and troubleshooting system prompt
- Configuration templates: Pre-built Cisco IOS, IOS-XE, Juniper, and Arista BGP configs for common topologies
- Troubleshooting decision tree: Step-by-step flowchart for diagnosing neighbor, convergence, and filtering issues
- Configuration validation checklist: Pre-flight checks for BGP security, timers, and redundancy
- Route filtering templates: Standard route-maps and prefix-lists for common scenarios
- Common misconfigurations guide: Reference of 20+ known issues (missing update-source, wrong AS, etc.)
- Security hardening playbook: Best practices for route filtering, authentication, and hijacking prevention
Who It's For
- Network engineers managing BGP deployments and multi-site routing
- Network operations teams troubleshooting BGP neighbor and convergence issues
- BGP specialists optimizing routing policies and AS path strategies
- Service provider engineers supporting customer BGP sessions
- Route optimization specialists tuning failover and load balancing
Best For
- Validating BGP configurations before production deployment
- Diagnosing neighbor adjacency failures and state mismatches
- Troubleshooting missing or incorrect route propagation
- Analyzing and optimizing AS path prepending strategies
- Identifying BGP security vulnerabilities and hardening configurations







