Flux (GitOps tool) Amazon EKS - Part 1

Introduction

GitOps[1] tool, best practice Git Continuous Integration/Continuous Delivery (CI/CD) standard Software Development Life Cycle (SDLC) Infrastructure as Code (IaC) IT operation infrastructure

Flux[2] GitOps tool resource Kubernetes cluster version Flux v2 Flux operator cluster pull declarative (IaC) Git repository reconcile Kubernetes resource

blog post Flux

Prerequisites

• eksctl flux
• personal access token GitHub account

How to setup Flux on Amazon EKS cluster

eksctl[3] standard tool EKS cluster vesion 0.53.0 feature Flux

EKS cluster Flux

1. export
   

   export GITHUB_USERNAME=<your GitHub username>export GITHUB_TOKEN=<your GitHub personal access token>

2. config file code <GitHub username> GitHub username
   

   cat << EOF > eks-gitops-demo.yamlapiVersion: eksctl.io/v1alpha5kind: ClusterConfigmetadata:  name: eks-gitops-demo  region: ap-southeast-1managedNodeGroups:  - name: ng-1    instanceType: m5.large    desiredCapacity: 1gitops:  flux:    gitProvider: github    flags:      owner: "${GITHUB_USERNAME}"      personal: "true"      private: "true"      repository: "eks-gitops-demo"      branch: "master"      namespace: "flux-system"      path: "clusters/eks-gitops-demo"EOF

3. EKS cluster eksctl create cluster --config-file eks-gitops-demo.yaml cluster

4. resource Flux kubectl --namespace flux-system get all
   

5. GitHub account repository eks-gitops-demo commit Kubernetes manifest file Flux component
   

EKS cluster Flux

Note. EKS cluster Flux

• cluster eksctl Flux eksctl enable flux
• eksctl Flux flux CLI flux bootstrap

How to use Flux basic features

Flux

Kubernetes manifest file

1. clone GitHub repository Flux
   

   git clone [email protected]:${GITHUB_USERNAME}/eks-gitops-demo.gitcd eks-gitops-demo

2. Kubernetes manifest file nginx:1.14.2 deployment commit push GitHub
   

   mkdir -p clusters/eks-gitops-demo/default/nginxcat << EOF > clusters/eks-gitops-demo/default/nginx/deployment.yamlapiVersion: apps/v1kind: Deploymentmetadata:  name: nginx-deployment  labels:    app: nginxspec:  replicas: 3  selector:    matchLabels:      app: nginx  template:    metadata:      labels:        app: nginx    spec:      containers:      - name: nginx        image: nginx:1.14.2        ports:        - containerPort: 80EOFgit add clusters/eks-gitops-demo/default/nginx/deployment.yamlgit commit -m "Add Nginx deployment"git push

3. default config Flux pull GitHub 10 reconcile Kubernetes resource flux reconcile source git flux-system pull
   

4. Flux apply change Kubernetes deployment kubectl get deployment nginx-deployment
   

5. deployment manifest file nginx:1.15.0 commit push GitHub
   

   sed -i '' 's/1.14.2/1.15.0/' clusters/eks-gitops-demo/default/nginx/deployment.yamlgit add clusters/eks-gitops-demo/default/nginx/deployment.yamlgit commit -m "Change Nginx image to 1.15.0"git push

6. Flux reconcile deployment nginx:1.15.0
   

7.(Bonus) deployment manifest commit push GitHub Flux reconcile deployment nginx

Flux Helm

1. HelmRepository CRD Helm Chart repository prometheus-community
   

   mkdir -p clusters/eks-gitops-demo/monitoringcat << EOF > clusters/eks-gitops-demo/monitoring/namespace.yamlapiVersion: v1kind: Namespacemetadata:  name: monitoringEOF---cat << EOF > clusters/eks-gitops-demo/monitoring/prometheus-community.yamlapiVersion: source.toolkit.fluxcd.io/v1beta1kind: HelmRepositorymetadata:  name: prometheus-community  namespace: monitoringspec:  url: https://prometheus-community.github.io/helm-charts  interval: 10mEOF

2. HelmRelease CRD Flux deploy Chart kube-prometheus-stack commit push GitHub
   

   mkdir -p clusters/eks-gitops-demo/monitoringcat << EOF > clusters/eks-gitops-demo/monitoring/namespace.yamlapiVersion: v1kind: Namespacemetadata:  name: monitoringEOFcat << EOF > clusters/eks-gitops-demo/monitoring/kube-prometheus-stack.yamlapiVersion: helm.toolkit.fluxcd.io/v2beta1kind: HelmReleasemetadata:  name: kube-prometheus-stack  namespace: monitoringspec:  releaseName: kube-prometheus-stack  interval: 10m  chart:    spec:      chart: kube-prometheus-stack      sourceRef:        kind: HelmRepository        name: prometheus-community        namespace: monitoringEOFgit add clusters/eks-gitops-demo/monitoring/*git commit -m "Add Prometheus with Helm"git push

3. flux reconcile source git flux-system pull change GitHub HelmRelease CRD interval reconcile 10 flux --namespace monitoring reconcile helmrelease kube-prometheus-stack reconcile
   

4. reconcile resource Prometheus cluster Helm Chart Flux
   

Conclusion

GitOps Git, CI/CD IaC infrastructure manual process

Flux tool implement GitOps Kubernetes blog post Amazon EKS eksctl

Flux part 2 feature Flux

References

[1] https://www.gitops.tech/#what-is-gitops
[2] https://fluxcd.io/
[3] https://eksctl.io/
[4] https://helm.sh/