Grafana

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1 - Présentation

Grafana est la plateforme de visualisation et d'observabilité la plus populaire.

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2 - Installation

2.1 Docker

# docker-compose.yml
version: '3.8'
services:
  grafana:
    image: grafana/grafana:10.2.0
    ports:
      - "3000:3000"
    environment:
      - GF_SECURITY_ADMIN_PASSWORD=admin
      - GF_USERS_ALLOW_SIGN_UP=false
    volumes:
      - grafana_data:/var/lib/grafana
      - ./provisioning:/etc/grafana/provisioning
      
volumes:
  grafana_data:

2.2 Kubernetes

helm repo add grafana https://grafana.github.io/helm-charts
helm install grafana grafana/grafana \
    --namespace monitoring \
    --set adminPassword=admin \
    --set persistence.enabled=true

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3 - Data Sources

3.1 Provisioning

# provisioning/datasources/datasources.yml
apiVersion: 1

datasources:
  - name: Prometheus
    type: prometheus
    access: proxy
    url: http://prometheus:9090
    isDefault: true
    editable: false
    
  - name: Loki
    type: loki
    access: proxy
    url: http://loki:3100
    
  - name: Tempo
    type: tempo
    access: proxy
    url: http://tempo:3200
    jsonData:
      tracesToLogs:
        datasourceUid: loki
        tags: ['service.name']

3.2 Configuration par API

# Créer une data source via API
curl -X POST http://admin:admin@localhost:3000/api/datasources \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Prometheus",
    "type": "prometheus",
    "url": "http://prometheus:9090",
    "access": "proxy",
    "isDefault": true
  }'

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4 - Dashboards

4.1 Structure JSON

{
  "dashboard": {
    "title": "My Dashboard",
    "tags": ["monitoring", "production"],
    "timezone": "browser",
    "panels": [
      {
        "id": 1,
        "title": "Request Rate",
        "type": "timeseries",
        "gridPos": { "x": 0, "y": 0, "w": 12, "h": 8 },
        "targets": [
          {
            "expr": "rate(http_requests_total[5m])",
            "legendFormat": "{{method}} {{status}}"
          }
        ]
      }
    ],
    "templating": {
      "list": []
    },
    "time": {
      "from": "now-1h",
      "to": "now"
    }
  }
}

4.2 Provisioning Dashboards

# provisioning/dashboards/default.yml
apiVersion: 1

providers:
  - name: 'default'
    folder: 'Provisioned'
    type: file
    disableDeletion: true
    updateIntervalSeconds: 30
    options:
      path: /etc/grafana/provisioning/dashboards

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5 - Panels

5.1 Types de panels

Panel	Usage
Time series	Graphiques temporels
Stat	Valeur unique
Gauge	Jauge visuelle
Bar gauge	Barres
Table	Données tabulaires
Heatmap	Distribution
Logs	Affichage des logs

5.2 Time series

{
  "type": "timeseries",
  "fieldConfig": {
    "defaults": {
      "color": { "mode": "palette-classic" },
      "custom": {
        "drawStyle": "line",
        "lineInterpolation": "smooth",
        "fillOpacity": 20
      },
      "unit": "reqps"
    }
  },
  "options": {
    "legend": {
      "displayMode": "table",
      "placement": "bottom",
      "calcs": ["mean", "max", "last"]
    }
  }
}

5.3 Stat Panel

{
  "type": "stat",
  "fieldConfig": {
    "defaults": {
      "mappings": [],
      "thresholds": {
        "mode": "absolute",
        "steps": [
          { "color": "green", "value": null },
          { "color": "yellow", "value": 50 },
          { "color": "red", "value": 80 }
        ]
      },
      "unit": "percent"
    }
  },
  "options": {
    "colorMode": "value",
    "graphMode": "area",
    "justifyMode": "auto",
    "orientation": "horizontal"
  }
}

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6 - Variables (Templates)

6.1 Types de variables

variables:
  # Query variable
  - name: namespace
    type: query
    datasource: Prometheus
    query: label_values(kube_pod_info, namespace)
    refresh: on_time_range_change
    
  # Custom variable
  - name: environment
    type: custom
    options:
      - { text: "Production", value: "prod" }
      - { text: "Staging", value: "staging" }
    
  # Interval variable
  - name: interval
    type: interval
    options: ["1m", "5m", "15m", "1h"]
    auto: true
    auto_count: 30

6.2 Utilisation dans les queries

# Utiliser les variables
rate(http_requests_total{namespace="$namespace"}[$__interval])

# Multi-value
rate(http_requests_total{namespace=~"$namespace"}[5m])

6.3 Chained Variables

variables:
  - name: cluster
    query: label_values(kube_pod_info, cluster)
    
  - name: namespace
    query: label_values(kube_pod_info{cluster="$cluster"}, namespace)
    
  - name: pod
    query: label_values(kube_pod_info{cluster="$cluster", namespace="$namespace"}, pod)

---

7 - Alerting

7.1 Alert Rules

# Alert rule via provisioning
apiVersion: 1
groups:
  - name: http-alerts
    folder: HTTP
    interval: 1m
    rules:
      - uid: high-error-rate
        title: High Error Rate
        condition: B
        data:
          - refId: A
            relativeTimeRange:
              from: 300
              to: 0
            datasourceUid: prometheus
            model:
              expr: |
                sum(rate(http_requests_total{status=~"5.."}[5m])) 
                / sum(rate(http_requests_total[5m])) * 100
          - refId: B
            relativeTimeRange:
              from: 0
              to: 0
            datasourceUid: '-100'
            model:
              conditions:
                - evaluator:
                    params: [5]
                    type: gt
                  operator:
                    type: and
                  query:
                    params: [A]
                  reducer:
                    type: avg
        for: 5m
        labels:
          severity: critical
        annotations:
          summary: "Error rate above 5%"

7.2 Contact Points

# Contact point configuration
contactPoints:
  - name: slack-notifications
    receivers:
      - uid: slack
        type: slack
        settings:
          url: https://hooks.slack.com/services/xxx
          recipient: "#alerts"
          
  - name: pagerduty-critical
    receivers:
      - uid: pagerduty
        type: pagerduty
        settings:
          integrationKey: xxx
          severity: critical

7.3 Notification Policies

policies:
  - receiver: slack-notifications
    group_by: ['alertname', 'severity']
    group_wait: 30s
    group_interval: 5m
    repeat_interval: 4h
    routes:
      - receiver: pagerduty-critical
        matchers:
          - severity = critical
        continue: true

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8 - Dashboard Best Practices

8.1 Layout recommandé

┌─────────────────────────────────────────────────┐
│                    Variables                     │
├─────────────────────────────────────────────────┤
│ Request Rate │ Error Rate │ Latency P99 │ Uptime│  <- Stat panels
├─────────────────────────────────────────────────┤
│                                                 │
│              Request Rate Graph                 │  <- Time series
│                                                 │
├─────────────────────────────────────────────────┤
│                                                 │
│              Latency Distribution               │  <- Heatmap
│                                                 │
├─────────────────────────────────────────────────┤
│           Top Endpoints Table                   │  <- Table
└─────────────────────────────────────────────────┘

8.2 Conventions

Aspect	Recommandation
Couleurs	Vert=OK, Jaune=Warning, Rouge=Critical
Noms	Descriptifs, incluant l'unité
Requêtes	Utiliser des Recording Rules
Variables	Namespace, Environment, Service

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Résumé

Dans ce chapitre, nous avons appris :

• L'installation de Grafana
• La configuration des Data Sources
• La création de Dashboards
• Les différents types de Panels
• Les Variables et templates
• L'Alerting intégré
• Les bonnes pratiques

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Prochaine étape

Dans le prochain chapitre, nous verrons ELK Stack.

→ Chapitre suivant : ELK Stack

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