BGP routing incidents can cause immediate user impact: traffic detours, latency spikes, partial outages, and trust issues. The good news is that mid-size IT teams can build a practical early-warning system without buying a large routing analytics platform.
This playbook combines public route visibility with local router telemetry for fast, actionable detection.
What to detect first
- Origin hijack: your prefix appears with an unexpected origin ASN
- Route leak: path propagation is abnormal
- Policy drift: announcements are valid but no longer follow intended path controls
Data sources
- Public BGP collectors (RIPE RIS style visibility)
- Edge router telemetry from your BGP neighbors
- Synthetic probes from user regions
Public signals show global behavior. Local telemetry confirms business impact.
1) Build a known-good inventory
prefix,expected_origin_asn,authorized_upstreams,critical_service
203.0.113.0/24,AS64500,AS64496|AS64510,customer-portal
198.51.100.0/24,AS64500,AS64496|AS64510,api-gateway
Without this inventory, alerts become noise.
2) Alert on unauthorized origins first
if observed_prefix in owned_prefixes:
if observed_origin_asn not in expected_origin_asns[prefix]:
alert("CRITICAL possible origin hijack", prefix, observed_origin_asn)
This is high-confidence and high-impact, so route directly to on-call.
3) Correlate with router state
show ip bgp <prefix>
show bgp summary
show route <prefix> detail
- Did best path change unexpectedly?
- Did preferred upstream move?
- Are flap counters rising?
4) Add leak heuristics in phase 2
- Sudden AS-path length inflation
- Unexpected transit ASN appears
- Burst of path changes in short windows
Tune by criticality to avoid fatigue.
5) Pair detection with prevention
- Publish/maintain RPKI ROAs for your prefixes
- Enforce import/export route filtering policy
- Maintain escalation contacts with upstream providers
30-minute incident flow
- Confirm mismatch from at least two external viewpoints
- Validate local path and user impact
- Escalate to provider with prefix, ASN, timestamp, path sample
- Notify application owners
- Track normalization and error reduction
Metrics that matter
- MTTD for unauthorized origin events
- Time to provider escalation
- False-positive rate per prefix tier
- User-visible impact duration
Final takeaway: prefix inventory plus origin-AS mismatch detection gives immediate value and a repeatable response model for real routing incidents.
References
Operational Checklist (Production-Safe)
- Confirm prerequisites and permissions before changes.
- Apply the change in staging or a low-risk window first.
- Capture logs/output before and after to validate impact.
- Document rollback steps and owner responsibility.
- Re-verify service health and security controls after completion.
Validation and Success Criteria
- The target workflow completes without errors and without introducing service interruption.
- Expected security/availability behavior is confirmed through logs and direct functional tests.
- No unintended access, policy drift, or performance regression is observed after deployment.
Common Pitfalls to Avoid
- Applying changes without confirming exact environment prerequisites.
- Skipping post-change verification and relying only on command success output.
- Not defining rollback steps before touching production assets.