Flux CD GitOps Patterns

Implement GitOps best practices with Flux CD, including repository structure, dependency management, and deployment patterns.

Keywords

flux, fluxcd, gitops, patterns, architecture, repository, structure, kustomization, helmrelease, dependencies, multi-tenant, multi-cluster, secrets, sops, designing, creating, deployment, deployments, notification, alerts, alerting, reconciliation, interval

When to Use This Skill

• Designing GitOps repository structure
• Setting up dependency chains between resources
• Implementing multi-environment deployments
• Configuring secrets management with Flux
• Setting up notifications and alerts
• Optimizing reconciliation intervals

Related Skills

• flux-troubleshooting - Diagnosing issues
• flux-operations - Day-to-day operations
• k8s-platform-tenancy - Multi-tenant patterns

Quick Reference

Repository Patterns

Monorepo (Recommended for Small Teams)

homelab/
├── clusters/
│   ├── production/
│   │   ├── flux-system/
│   │   ├── infrastructure.yaml
│   │   └── apps.yaml
│   └── staging/
│       ├── flux-system/
│       └── ...
├── infrastructure/
│   ├── kustomization.yaml
│   ├── cert-manager/
│   ├── external-dns/
│   └── external-secrets/
├── apps/
│   ├── kustomization.yaml
│   ├── grafana/
│   └── loki/
└── helm/
    └── local-charts/

Multi-Repo (Enterprise)

fleet-infra/          # Flux bootstrap, cluster configs
├── clusters/
│   ├── production/
│   └── staging/

platform-components/  # Shared infrastructure
├── cert-manager/
├── ingress-nginx/
└── monitoring/

team-alpha-apps/      # Team-specific apps
├── app1/
└── app2/

Component Structure

component-name/
├── namespace.yaml       # Namespace isolation
├── repository.yaml      # HelmRepository source
├── release.yaml         # HelmRelease deployment
└── kustomization.yaml   # Resource orchestration

Dependency Management

Kustomization Dependencies

apiVersion: kustomize.toolkit.fluxcd.io/v1
kind: Kustomization
metadata:
  name: apps
  namespace: flux-system
spec:
  dependsOn:
    - name: infrastructure
    - name: configs
  interval: 10m
  path: ./apps
  prune: true
  wait: true
  sourceRef:
    kind: GitRepository
    name: flux-system

Deployment Order

Flux System (bootstrapped)
  └─> Infrastructure (CRDs, operators)
      ├─> Configs (ConfigMaps, Secrets)
      └─> Monitoring (Prometheus, Grafana)
          └─> Apps (depends on all above)

Source Configuration

GitRepository

apiVersion: source.toolkit.fluxcd.io/v1
kind: GitRepository
metadata:
  name: flux-system
  namespace: flux-system
spec:
  interval: 10m
  url: https://github.com/org/repo
  ref:
    branch: main
  secretRef:
    name: flux-system
  ignore: |
    /*
    !/clusters/
    !/infrastructure/
    !/apps/

OCI Repository

apiVersion: source.toolkit.fluxcd.io/v1beta2
kind: OCIRepository
metadata:
  name: podinfo
  namespace: flux-system
spec:
  interval: 10m
  url: oci://ghcr.io/stefanprodan/manifests/podinfo
  ref:
    tag: latest
  provider: generic  # or aws, azure, gcp

HelmRepository

apiVersion: source.toolkit.fluxcd.io/v1
kind: HelmRepository
metadata:
  name: bitnami
  namespace: flux-system
spec:
  interval: 30m
  url: https://charts.bitnami.com/bitnami

Variable Substitution

Environment Variables

apiVersion: kustomize.toolkit.fluxcd.io/v1
kind: Kustomization
spec:
  postBuild:
    substitute:
      CLUSTER_NAME: production
      DOMAIN: example.com
      ENVIRONMENT: prod
    substituteFrom:
      - kind: ConfigMap
        name: cluster-vars
      - kind: Secret
        name: cluster-secrets

Usage in Manifests

apiVersion: networking.k8s.io/v1
kind: Ingress
spec:
  rules:
    - host: app.${DOMAIN}  # Substituted

Secrets Management

SOPS Integration

apiVersion: kustomize.toolkit.fluxcd.io/v1
kind: Kustomization
spec:
  decryption:
    provider: sops
    secretRef:
      name: sops-age  # Contains age private key

External Secrets Pattern

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: app-secrets
spec:
  refreshInterval: 1h
  secretStoreRef:
    kind: ClusterSecretStore
    name: vault
  target:
    name: app-secrets
    creationPolicy: Owner
  data:
    - secretKey: db-password
      remoteRef:
        key: secret/data/app
        property: password

Notification Patterns

Provider Configuration

apiVersion: notification.toolkit.fluxcd.io/v1beta3
kind: Provider
metadata:
  name: discord
  namespace: flux-system
spec:
  type: discord
  secretRef:
    name: discord-webhook

Alert Configuration

apiVersion: notification.toolkit.fluxcd.io/v1beta3
kind: Alert
metadata:
  name: on-call-alerts
  namespace: flux-system
spec:
  providerRef:
    name: discord
  eventSeverity: error
  eventSources:
    - kind: GitRepository
      name: '*'
    - kind: Kustomization
      name: '*'
    - kind: HelmRelease
      name: '*'
      namespace: '*'

Interval Guidelines

GitOps Principles

1. Declarative - Desired state in Git, not imperative commands
2. Versioned - All changes tracked in Git history
3. Automated - Flux applies changes automatically
4. Auditable - Git log provides complete audit trail
5. Self-healing - Drift automatically corrected

Anti-Patterns to Avoid