Service Mesh Observability

Complete guide to observability patterns for Istio, Linkerd, and service mesh deployments.

When to Use This Skill

• Setting up distributed tracing across services
• Implementing service mesh metrics and dashboards
• Debugging latency and error issues
• Defining SLOs for service communication
• Visualizing service dependencies
• Troubleshooting mesh connectivity

Core Concepts

1. Three Pillars of Observability

┌─────────────────────────────────────────────────────┐
│                  Observability                       │
├─────────────────┬─────────────────┬─────────────────┤
│     Metrics     │     Traces      │      Logs       │
│                 │                 │                 │
│ • Request rate  │ • Span context  │ • Access logs   │
│ • Error rate    │ • Latency       │ • Error details │
│ • Latency P50   │ • Dependencies  │ • Debug info    │
│ • Saturation    │ • Bottlenecks   │ • Audit trail   │
└─────────────────┴─────────────────┴─────────────────┘

2. Golden Signals for Mesh

Signal	Description	Alert Threshold
Latency	Request duration P50, P99	P99 > 500ms
Traffic	Requests per second	Anomaly detection
Errors	5xx error rate	> 1%
Saturation	Resource utilization	> 80%

Templates and detailed worked examples

Full template library and detailed worked examples live in references/details.md. Read that file when you need the concrete templates.

Best Practices

Do's

• Sample appropriately - 100% in dev, 1-10% in prod
• Use trace context - Propagate headers consistently
• Set up alerts - For golden signals
• Correlate metrics/traces - Use exemplars
• Retain strategically - Hot/cold storage tiers

Don'ts

• Don't over-sample - Storage costs add up
• Don't ignore cardinality - Limit label values
• Don't skip dashboards - Visualize dependencies
• Don't forget costs - Monitor observability costs