exa-advanced-troubleshooting

# Exa Advanced Troubleshooting

## Overview
Deep debugging techniques for complex Exa issues that resist standard troubleshooting.

## Prerequisites
- Access to production logs and metrics
- kubectl access to clusters
- Network capture tools available
- Understanding of distributed tracing

## Evidence Collection Framework

### Comprehensive Debug Bundle
```bash
#!/bin/bash
# advanced-exa-debug.sh

BUNDLE="exa-advanced-debug-$(date +%Y%m%d-%H%M%S)"
mkdir -p "$BUNDLE"/{logs,metrics,network,config,traces}

# 1. Extended logs (1 hour window)
kubectl logs -l app=exa-integration --since=1h > "$BUNDLE/logs/pods.log"
journalctl -u exa-service --since "1 hour ago" > "$BUNDLE/logs/system.log"

# 2. Metrics dump
curl -s localhost:9090/api/v1/query?query=exa_requests_total > "$BUNDLE/metrics/requests.json"
curl -s localhost:9090/api/v1/query?query=exa_errors_total > "$BUNDLE/metrics/errors.json"

# 3. Network capture (30 seconds)
timeout 30 tcpdump -i any port 443 -w "$BUNDLE/network/capture.pcap" &

# 4. Distributed traces
curl -s localhost:16686/api/traces?service=exa > "$BUNDLE/traces/jaeger.json"

# 5. Configuration state
kubectl get cm exa-config -o yaml > "$BUNDLE/config/configmap.yaml"
kubectl get secret exa-secrets -o yaml > "$BUNDLE/config/secrets-redacted.yaml"

tar -czf "$BUNDLE.tar.gz" "$BUNDLE"
echo "Advanced debug bundle: $BUNDLE.tar.gz"
```

## Systematic Isolation

### Layer-by-Layer Testing

```typescript
// Test each layer independently
async function diagnoseExaIssue(): Promise<DiagnosisReport> {
  const results: DiagnosisResult[] = [];

  // Layer 1: Network connectivity
  results.push(await testNetworkConnectivity());

  // Layer 2: DNS resolution
  results.push(await testDNSResolution('api.exa.com'));

  // Layer 3: TLS handshake
  results.push(await testTLSHandshake('api.exa.com'));

  // Layer 4: Authentication
  results.push(await testAuthentication());

  // Layer 5: API response
  results.push(await testAPIResponse());

  // Layer 6: Response parsing