Observability & Monitoring

You cannot manage what you cannot see. Observability in Kubernetes covers three pillars: metrics, logs, and traces. This lesson covers the Prometheus/Grafana monitoring stack, logging with Fluentd and Loki, distributed tracing with Jaeger, and alerting strategies.

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The Three Pillars of Observability

Pillar	What It Answers	Tools
Metrics	How is the system performing?	Prometheus, Grafana, metrics-server
Logs	What happened and why?	Fluentd, Loki, Elasticsearch
Traces	How does a request flow through services?	Jaeger, Zipkin, Tempo

┌─────────────────────────────────────────────────────────────┐
│                        Grafana                              │
│                   (Unified Dashboard)                       │
└──────┬──────────────────┬──────────────────┬────────────────┘
       │                  │                  │
       ▼                  ▼                  ▼
┌────────────┐    ┌────────────┐    ┌────────────┐
│ Prometheus │    │   Loki     │    │   Jaeger   │
│  (Metrics) │    │  (Logs)    │    │  (Traces)  │
└──────┬─────┘    └──────┬─────┘    └──────┬─────┘
       │                 │                 │
       ▼                 ▼                 ▼
┌────────────┐    ┌────────────┐    ┌────────────┐
│ Exporters  │    │  Fluentd / │    │ OpenTelemetry│
│ /metrics   │    │  Promtail  │    │    SDK      │
└────────────┘    └────────────┘    └────────────┘

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Prometheus — Metrics Collection

Prometheus is the de-facto standard for Kubernetes metrics.

Installing with kube-prometheus-stack

helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
helm repo update