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diff --git a/gemfeed/DRAFT-f3s-kubernetes-with-freebsd-part-X.gmi.tpl b/gemfeed/DRAFT-f3s-kubernetes-with-freebsd-part-X.gmi.tpl new file mode 100644 index 00000000..c916a3f9 --- /dev/null +++ b/gemfeed/DRAFT-f3s-kubernetes-with-freebsd-part-X.gmi.tpl @@ -0,0 +1,992 @@ +# f3s: Kubernetes with FreeBSD - Part X: GitOps with ArgoCD + +> DRAFT - Not yet published + +This is part X of the f3s series for my self-hosting demands in a home lab. f3s? The "f" stands for FreeBSD, and the "3s" stands for k3s, the Kubernetes distribution I use on FreeBSD-based physical machines. + +<< template::inline::index f3s-kubernetes-with-freebsd-part + +=> ./f3s-kubernetes-with-freebsd-part-1/f3slogo.png f3s logo + +<< template::inline::toc + +## Introduction + +In the previous posts, I deployed applications to the k3s cluster using Helm charts and Justfiles—running `just install` or `just upgrade` to imperatively push changes to the cluster. While this approach works, it has several drawbacks: + +* **No single source of truth**: The cluster state depends on which commands were run and when +* **Manual synchronization**: Every change requires manually running commands +* **Drift detection is hard**: No easy way to know if cluster state matches the desired configuration +* **Rollback complexity**: Rolling back changes means re-running old Helm commands +* **No audit trail**: Hard to track who changed what and when + +This blog post covers the migration from imperative Helm deployments to declarative GitOps using ArgoCD. After this migration, the Git repository becomes the single source of truth, and ArgoCD automatically ensures the cluster matches what's defined in Git. + +## What is GitOps? + +GitOps is an operational framework that applies DevOps best practices—like version control, collaboration, and CI/CD—to infrastructure automation. The core idea is simple: the entire desired state of your infrastructure is stored in Git, and automated processes ensure the actual state matches the desired state. + +Key principles: + +* **Declarative**: The system's desired state is described declaratively (YAML manifests, Helm values) +* **Versioned and immutable**: All changes are committed to Git, providing a complete history +* **Pulled automatically**: An agent in the cluster continuously pulls the desired state from Git +* **Continuously reconciled**: The agent ensures the actual state matches the desired state, automatically correcting drift + +For Kubernetes, this means: + +1. All manifests, Helm charts, and configuration live in a Git repository +2. A tool (ArgoCD in our case) watches the repository +3. When changes are pushed to Git, ArgoCD automatically applies them to the cluster +4. If someone manually changes resources in the cluster, ArgoCD detects the drift and can automatically revert it + +## What is ArgoCD? + +ArgoCD is a declarative, GitOps continuous delivery tool for Kubernetes. It's implemented as a Kubernetes controller that continuously monitors running applications and compares the current, live state against the desired target state defined in Git. + +=> https://argo-cd.readthedocs.io ArgoCD Documentation + +Key features: + +* **Automated deployment**: Monitors Git repositories and automatically syncs changes to the cluster +* **Application definitions**: Defines applications as CRDs (Custom Resource Definitions) +* **Health assessment**: Understands Kubernetes resources and can determine if an application is healthy +* **Web UI and CLI**: Provides both a web interface and command-line tool for managing applications +* **RBAC**: Role-based access control for team collaboration +* **SSO integration**: Can integrate with existing authentication systems +* **Multi-cluster support**: Can manage applications across multiple Kubernetes clusters +* **Sync waves and hooks**: Control the order of resource deployment and run jobs at specific lifecycle points + +## Why ArgoCD for f3s? + +For a home lab cluster, ArgoCD provides several benefits: + +**Disaster recovery**: If the entire cluster is lost, I can rebuild it by: +1. Bootstrapping a new k3s cluster +2. Installing ArgoCD +3. Pointing ArgoCD at the Git repository +4. All applications automatically deploy to the desired state + +**Experimentation safety**: I can test changes in a separate Git branch without affecting the running cluster. Once validated, merge to master and ArgoCD applies the changes. + +**Drift detection**: If I manually change something in the cluster (for debugging), ArgoCD shows the difference and can automatically revert it. + +**Declarative configuration**: The Git repository documents the entire cluster configuration. No need to remember which `just` commands to run or in which order. + +**Automatic sync**: Push to Git, and changes deploy automatically. No need to SSH to a workstation and run Helm commands. + +## Deploying ArgoCD + +ArgoCD itself runs as a set of Kubernetes resources in the cluster. The official installation method uses `kubectl apply`, which is fitting—ArgoCD manages everything else via GitOps, but ArgoCD itself needs a bootstrap. + +### Prerequisites + +Create the `cicd` namespace where ArgoCD will run: + +```sh +$ kubectl create namespace cicd +namespace/cicd created +``` + +### Installing ArgoCD + +The ArgoCD installation lives in the configuration repository: + +=> https://codeberg.org/snonux/conf/src/branch/master/f3s/argocd codeberg.org/snonux/conf/f3s/argocd + +I deployed ArgoCD using Helm instead of the raw manifests. This provides easier upgrades and customization. The installation is managed via a Justfile: + +```sh +$ cd conf/f3s/argocd +$ just install +helm repo add argo https://argoproj.github.io/argo-helm +helm repo update +helm install argocd argo/argo-cd \ + --namespace cicd \ + --version 7.7.12 \ + -f values.yaml +NAME: argocd +LAST DEPLOYED: ... +NAMESPACE: cicd +STATUS: deployed +``` + +The `values.yaml` file configures several important aspects: + +**Persistent storage for the repo-server**: ArgoCD clones Git repositories to cache them locally. I configured a persistent volume so the cache survives pod restarts: + +```yaml +repoServer: + volumes: + - name: repo-cache + persistentVolumeClaim: + claimName: argocd-repo-cache-pvc + volumeMounts: + - name: repo-cache + mountPath: /tmp +``` + +**Admin password preservation**: By default, the admin password is auto-generated and stored in a secret. To ensure it persists across Helm upgrades: + +```yaml +configs: + secret: + createSecret: false +``` + +I manually created the secret before installation: + +```sh +$ ARGOCD_ADMIN_PASSWORD=$(pwgen -s 32 1) +$ BCRYPT_HASH=$(htpasswd -nbBC 10 "" "$ARGOCD_ADMIN_PASSWORD" | tr -d ':\n' | sed 's/$2y/$2a/') +$ kubectl create secret generic argocd-secret \ + --from-literal=admin.password="$BCRYPT_HASH" \ + -n cicd +$ echo "ArgoCD admin password: $ARGOCD_ADMIN_PASSWORD" +``` + +**Server configuration**: Enabled insecure mode since TLS is handled by the OpenBSD edge relays: + +```yaml +server: + insecure: true +``` + +### Accessing ArgoCD + +After deployment, ArgoCD runs several pods in the `cicd` namespace: + +```sh +$ kubectl get pods -n cicd +NAME READY STATUS RESTARTS AGE +argocd-application-controller-0 1/1 Running 0 45d +argocd-applicationset-controller-66d6b9b8f4-vhm9k 1/1 Running 0 45d +argocd-dex-server-7fb556b7dd-xjr2l 1/1 Running 0 45d +argocd-notifications-controller-6d8dd4c5f5-b8vwl 1/1 Running 0 45d +argocd-redis-77b8d6c6d4-mz9hg 1/1 Running 0 45d +argocd-repo-server-5f98f77b97-8xtcq 1/1 Running 0 45d +argocd-server-6b9c4b4f8d-kxw7p 1/1 Running 0 45d +``` + +I created an ingress to expose the ArgoCD web UI: + +```yaml +apiVersion: networking.k8s.io/v1 +kind: Ingress +metadata: + name: argocd-server-ingress + namespace: cicd + annotations: + spec.ingressClassName: traefik + traefik.ingress.kubernetes.io/router.entrypoints: web +spec: + rules: + - host: argocd.f3s.buetow.org + http: + paths: + - path: / + pathType: Prefix + backend: + service: + name: argocd-server + port: + number: 80 +``` + +Following the same pattern as other services, the OpenBSD edge relays terminate TLS and forward traffic through WireGuard to the cluster. ArgoCD is now accessible at: + +=> https://argocd.f3s.buetow.org ArgoCD Web UI + +The ArgoCD CLI can also be used for operations: + +```sh +$ argocd login argocd.f3s.buetow.org +$ argocd app list +``` + +## ArgoCD Application Structure + +ArgoCD uses a CRD called `Application` to define what should be deployed. Each application specifies: + +* **Source**: Where the manifests live (Git repo, Helm chart repository, or both) +* **Destination**: Which cluster and namespace to deploy to +* **Sync policy**: Whether to automatically sync changes + +Here's a simple example for the miniflux application: + +```yaml +apiVersion: argoproj.io/v1alpha1 +kind: Application +metadata: + name: miniflux + namespace: cicd + finalizers: + - resources-finalizer.argocd.argoproj.io +spec: + project: default + source: + repoURL: https://codeberg.org/snonux/conf.git + targetRevision: master + path: f3s/miniflux/helm-chart + destination: + server: https://kubernetes.default.svc + namespace: services + syncPolicy: + automated: + prune: true + selfHeal: true + syncOptions: + - CreateNamespace=false + retry: + limit: 3 + backoff: + duration: 5s + factor: 2 + maxDuration: 1m +``` + +Key fields: + +* `source.path`: Points to the Helm chart directory in Git +* `destination.namespace`: Where to deploy the application +* `syncPolicy.automated.prune`: Delete resources that are removed from Git +* `syncPolicy.automated.selfHeal`: Automatically revert manual changes in the cluster +* `finalizers`: Ensures ArgoCD deletes all resources when the Application is deleted + +## Repository Organization + +I reorganized the configuration repository to support GitOps: + +``` +/home/paul/git/conf/f3s/ +├── argocd-apps/ # ArgoCD Application manifests +│ ├── anki-sync-server.yaml +│ ├── miniflux.yaml +│ ├── prometheus.yaml +│ ├── loki.yaml +│ ├── ... +│ └── (21 Application manifests total) +├── miniflux/ # Application directories (unchanged) +│ ├── helm-chart/ +│ │ ├── Chart.yaml +│ │ ├── values.yaml +│ │ └── templates/ +│ └── Justfile # Updated for ArgoCD +├── prometheus/ +│ ├── manifests/ # NEW: Additional manifests +│ │ ├── persistent-volumes.yaml +│ │ ├── grafana-restart-hook.yaml +│ │ ├── freebsd-recording-rules.yaml +│ │ └── ... +│ └── Justfile # Updated for ArgoCD +└── ... +``` + +The application directories (miniflux, prometheus, etc.) remained mostly unchanged—ArgoCD references the same Helm charts. The main additions: + +1. **argocd-apps/**: Application manifests that ArgoCD reads +2. ***/manifests/**: Additional Kubernetes manifests for complex apps (like Prometheus) +3. **Justfiles updated**: Changed from `helm install/upgrade` to `argocd app sync` + +## Migration Strategy: Incremental, One App at a Time + +Rather than attempting a "big bang" migration of all 21 applications at once, I migrated them incrementally: + +1. **Start with a simple app**: Validate the pattern with a low-risk application +2. **Migrate in waves**: Group similar applications and migrate together +3. **Validate thoroughly**: Ensure each app is healthy before moving to the next +4. **Learn and iterate**: Apply lessons from earlier migrations to later ones + +This approach reduced risk and allowed me to refine the migration process. + +### Migration Phases + +**Phase 1: Simple services** (13 apps) +* miniflux, freshrss, wallabag +* anki-sync-server, kobo-sync-server, opodsync +* radicale, syncthing, audiobookshelf +* filebrowser, keybr, webdav +* example-apache, example-apache-volume-claim + +These apps have straightforward Helm charts with no complex dependencies. Pattern established: +1. Create Application manifest in `argocd-apps/` +2. Apply with `kubectl apply -f argocd-apps/<app>.yaml` +3. Verify sync status: `argocd app get <app>` +4. Update Justfile to use ArgoCD commands + +**Phase 2: Infrastructure apps** (3 apps) +* registry (Docker image registry) +* pushgateway (Prometheus metrics ingestion) +* immich (photo management with complex dependencies) + +**Phase 3: Monitoring stack** (4 apps) +* tempo (distributed tracing) +* loki (log aggregation) +* alloy (log collection) +* prometheus (metrics and monitoring) + +**Phase 4: Monitoring addons** (1 app) +* grafana-ingress (separate ingress for Grafana) + +## Example Migration: Miniflux + +Let me walk through the migration of miniflux as a concrete example. + +### Before: Imperative Helm deployment + +Original Justfile: + +```makefile +NAMESPACE := "services" +APP_NAME := "miniflux" + +install: + kubectl apply -f helm-chart/persistent-volumes.yaml + helm install {{APP_NAME}} ./helm-chart --namespace {{NAMESPACE}} + +upgrade: + helm upgrade {{APP_NAME}} ./helm-chart --namespace {{NAMESPACE}} + +uninstall: + helm uninstall {{APP_NAME}} --namespace {{NAMESPACE}} + kubectl delete -f helm-chart/persistent-volumes.yaml + +status: + @kubectl get all -n {{NAMESPACE}} -l app={{APP_NAME}} +``` + +Workflow: +1. Make changes to `helm-chart/` +2. Run `just upgrade` +3. Helm pushes changes to cluster + +### After: Declarative GitOps with ArgoCD + +Created `argocd-apps/miniflux.yaml`: + +```yaml +apiVersion: argoproj.io/v1alpha1 +kind: Application +metadata: + name: miniflux + namespace: cicd + finalizers: + - resources-finalizer.argocd.argoproj.io +spec: + project: default + source: + repoURL: https://codeberg.org/snonux/conf.git + targetRevision: master + path: f3s/miniflux/helm-chart + destination: + server: https://kubernetes.default.svc + namespace: services + syncPolicy: + automated: + prune: true + selfHeal: true + syncOptions: + - CreateNamespace=false + retry: + limit: 3 + backoff: + duration: 5s + factor: 2 + maxDuration: 1m +``` + +Updated Justfile: + +```makefile +NAMESPACE := "services" +APP_NAME := "miniflux" + +status: + @echo "=== Pods ===" + @kubectl get pods -n {{NAMESPACE}} -l app={{APP_NAME}} + @echo "" + @echo "=== Services ===" + @kubectl get svc -n {{NAMESPACE}} -l app={{APP_NAME}} + @echo "" + @echo "=== ArgoCD Status ===" + @kubectl get application {{APP_NAME}} -n cicd -o jsonpath='Sync: {.status.sync.status}, Health: {.status.health.status}' 2>/dev/null && echo "" + +sync: + @echo "Triggering ArgoCD sync..." + @kubectl annotate application {{APP_NAME}} -n cicd argocd.argoproj.io/refresh=normal --overwrite + @sleep 2 + @kubectl get application {{APP_NAME}} -n cicd -o jsonpath='Sync: {.status.sync.status}, Health: {.status.health.status}' && echo "" + +argocd-status: + argocd app get {{APP_NAME}} --core + +logs: + kubectl logs -n {{NAMESPACE}} -l app={{APP_NAME}} --tail=100 -f +``` + +New workflow: +1. Make changes to `helm-chart/` +2. Commit and push to Git +3. ArgoCD automatically detects and syncs changes +4. (Optional) Run `just sync` to force immediate sync + +### Migration procedure + +1. **Backup current state**: +```sh +$ helm get values miniflux -n services > /tmp/miniflux-backup-values.yaml +$ kubectl get all,ingress -n services -o yaml > /tmp/miniflux-backup.yaml +``` + +2. **Create Application manifest**: +```sh +$ kubectl apply -f argocd-apps/miniflux.yaml +application.argoproj.io/miniflux created +``` + +3. **Verify ArgoCD adopted the resources**: +```sh +$ argocd app get miniflux +Name: miniflux +Project: default +Server: https://kubernetes.default.svc +Namespace: services +URL: https://argocd.f3s.buetow.org/applications/miniflux +Repo: https://codeberg.org/snonux/conf.git +Target: master +Path: f3s/miniflux/helm-chart +SyncWindow: Sync Allowed +Sync Policy: Automated (Prune) +Sync Status: Synced to master (4e3c216) +Health Status: Healthy +``` + +4. **Monitor for issues**: +```sh +$ kubectl get pods -n services -l app=miniflux -w +NAME READY STATUS RESTARTS AGE +miniflux-postgres-556444cb8d-xvv2p 1/1 Running 0 54d +miniflux-server-85d7c64664-stmt9 1/1 Running 0 54d +``` + +5. **Test the application**: +```sh +$ curl -I https://flux.f3s.buetow.org +HTTP/2 200 +``` + +6. **Update Justfile** and commit changes + +Total time: 10 minutes. Zero downtime. + +## Complex Migration: Prometheus with Multi-Source + +The Prometheus migration was more complex because it combines: +* Upstream Helm chart (kube-prometheus-stack) +* Custom manifests (PersistentVolumes, recording rules, dashboards) +* Sync hooks (PostSync job to restart Grafana) + +ArgoCD supports "multi-source" Applications that combine multiple sources: + +```yaml +apiVersion: argoproj.io/v1alpha1 +kind: Application +metadata: + name: prometheus + namespace: cicd + finalizers: + - resources-finalizer.argocd.argoproj.io +spec: + project: default + sources: + # Source 1: Upstream Helm chart from prometheus-community + - repoURL: https://prometheus-community.github.io/helm-charts + chart: kube-prometheus-stack + targetRevision: 55.5.0 + helm: + releaseName: prometheus + valuesObject: + # Full Prometheus configuration embedded here + kubeEtcd: + enabled: true + endpoints: + - 192.168.2.120 + - 192.168.2.121 + - 192.168.2.122 + # ... (hundreds of lines of configuration) + + # Source 2: Additional manifests from Git repository + - repoURL: https://codeberg.org/snonux/conf.git + targetRevision: master + path: f3s/prometheus/manifests + + destination: + server: https://kubernetes.default.svc + namespace: monitoring + + syncPolicy: + automated: + prune: false # Manual pruning for safety on complex stack + selfHeal: true + syncOptions: + - CreateNamespace=false + - ServerSideApply=true + retry: + limit: 3 + backoff: + duration: 10s + factor: 2 + maxDuration: 3m +``` + +The `prometheus/manifests/` directory contains: + +``` +f3s/prometheus/manifests/ +├── persistent-volumes.yaml # Sync wave 0 +├── additional-scrape-configs-secret.yaml # Sync wave 1 +├── grafana-datasources-configmap.yaml # Sync wave 1 +├── freebsd-recording-rules.yaml # Sync wave 3 +├── openbsd-recording-rules.yaml # Sync wave 3 +├── zfs-recording-rules.yaml # Sync wave 3 +├── epimetheus-dashboard.yaml # Sync wave 4 +├── zfs-dashboards.yaml # Sync wave 4 +├── grafana-restart-hook.yaml # Sync wave 10 (PostSync) +└── grafana-restart-rbac.yaml # Sync wave 0 +``` + +### Sync Waves and Hooks + +ArgoCD allows controlling the order of resource deployment using sync waves (the `argocd.argoproj.io/sync-wave` annotation): + +* **Wave 0**: Infrastructure (PersistentVolumes, RBAC) +* **Wave 1**: Configuration (Secrets, ConfigMaps) +* **Wave 3**: Recording rules (PrometheusRule CRDs) +* **Wave 4**: Dashboards (ConfigMaps with `grafana_dashboard: '1'` label) +* **Wave 10**: PostSync hooks (Jobs that run after everything else) + +The Grafana restart hook ensures Grafana reloads datasources after they're updated: + +```yaml +apiVersion: batch/v1 +kind: Job +metadata: + name: grafana-restart-hook + namespace: monitoring + annotations: + argocd.argoproj.io/hook: PostSync + argocd.argoproj.io/hook-delete-policy: BeforeHookCreation + argocd.argoproj.io/sync-wave: "10" +spec: + template: + spec: + serviceAccountName: grafana-restart-sa + restartPolicy: OnFailure + containers: + - name: kubectl + image: bitnami/kubectl:latest + command: + - /bin/sh + - -c + - | + kubectl wait --for=condition=available --timeout=300s deployment/prometheus-grafana -n monitoring || true + kubectl delete pod -n monitoring -l app.kubernetes.io/name=grafana --ignore-not-found=true + backoffLimit: 2 +``` + +This replaces the manual step in the old Justfile that required running `kubectl delete pod` after every upgrade. + +## Migration Results + +After migrating all 21 applications to ArgoCD: + +```sh +$ argocd app list +NAME CLUSTER NAMESPACE PROJECT STATUS HEALTH SYNCPOLICY +alloy https://kubernetes.default.svc monitoring default Synced Healthy Auto-Prune +anki-sync-server https://kubernetes.default.svc services default Synced Healthy Auto-Prune +audiobookshelf https://kubernetes.default.svc services default Synced Healthy Auto-Prune +example-apache https://kubernetes.default.svc test default Synced Healthy Auto-Prune +example-apache-volume-... https://kubernetes.default.svc test default Synced Healthy Auto-Prune +filebrowser https://kubernetes.default.svc services default Synced Healthy Auto-Prune +freshrss https://kubernetes.default.svc services default Synced Healthy Auto-Prune +grafana-ingress https://kubernetes.default.svc monitoring default Synced Healthy Auto-Prune +immich https://kubernetes.default.svc services default Synced Healthy Auto-Prune +keybr https://kubernetes.default.svc services default Synced Healthy Auto-Prune +kobo-sync-server https://kubernetes.default.svc services default Synced Healthy Auto-Prune +loki https://kubernetes.default.svc monitoring default Synced Healthy Auto-Prune +miniflux https://kubernetes.default.svc services default Synced Healthy Auto-Prune +opodsync https://kubernetes.default.svc services default Synced Healthy Auto-Prune +prometheus https://kubernetes.default.svc monitoring default Synced Healthy Auto +pushgateway https://kubernetes.default.svc monitoring default Synced Healthy Auto-Prune +radicale https://kubernetes.default.svc services default Synced Healthy Auto-Prune +registry https://kubernetes.default.svc infra default Synced Healthy Auto-Prune +syncthing https://kubernetes.default.svc services default Synced Healthy Auto-Prune +tempo https://kubernetes.default.svc monitoring default Synced Healthy Auto-Prune +wallabag https://kubernetes.default.svc services default Synced Healthy Auto-Prune +webdav https://kubernetes.default.svc services default Synced Healthy Auto-Prune +``` + +All 21 applications: **Synced** and **Healthy**. + +ArgoCD Web UI: + +=> ./f3s-kubernetes-with-freebsd-part-X/argocd-apps-list.png ArgoCD Applications List + +=> ./f3s-kubernetes-with-freebsd-part-X/argocd-app-tree.png ArgoCD Application Resource Tree + +## Benefits Realized + +### 1. Single Source of Truth + +The Git repository at `https://codeberg.org/snonux/conf` now contains the complete cluster configuration. Anyone can clone it and see exactly what's deployed: + +```sh +$ git clone https://codeberg.org/snonux/conf.git +$ cd conf/f3s +$ ls argocd-apps/ +alloy.yaml anki-sync-server.yaml audiobookshelf.yaml ... +``` + +### 2. Automatic Synchronization + +Push to Git, and changes deploy automatically: + +```sh +$ cd conf/f3s/miniflux/helm-chart +$ vim values.yaml # Change replica count from 1 to 2 +$ git add values.yaml +$ git commit -m "Scale miniflux to 2 replicas" +$ git push +# ArgoCD detects change within 3 minutes and syncs automatically +``` + +No need to SSH to a workstation, pull the repo, and run `just upgrade`. + +### 3. Drift Detection and Self-Healing + +If someone manually changes a resource in the cluster, ArgoCD detects it: + +```sh +$ kubectl scale deployment miniflux-server -n services --replicas=3 +deployment.apps/miniflux-server scaled + +# ArgoCD detects drift within 3 minutes +$ argocd app get miniflux +... +Sync Status: OutOfSync from master (4e3c216) +``` + +With `selfHeal: true`, ArgoCD automatically reverts the change back to 2 replicas (the value in Git). + +### 4. Easy Rollbacks + +To rollback a change: + +```sh +$ git revert HEAD +$ git push +# ArgoCD automatically rolls back to the previous state +``` + +Or rollback to a specific commit: + +```sh +$ argocd app rollback miniflux <revision-id> +``` + +### 5. Disaster Recovery + +If the entire cluster is destroyed, recovery is straightforward: + +1. Bootstrap a new k3s cluster +2. Create namespaces +3. Install ArgoCD +4. Apply all Application manifests: +```sh +$ kubectl apply -f argocd-apps/ +``` +5. ArgoCD deploys all 21 applications to their desired state + +Total recovery time: ~30 minutes (mostly waiting for pods to pull images and start). + +### 6. Documentation by Default + +The Application manifests serve as documentation: + +* Which Helm chart version is deployed? → Check `targetRevision` +* What custom values are configured? → Check `valuesObject` +* Which namespace does this deploy to? → Check `destination.namespace` +* Is auto-sync enabled? → Check `syncPolicy.automated` + +No more guessing or checking `helm list` output. + +### 7. Safe Experimentation + +Create a feature branch, make changes, and preview them: + +```sh +$ git checkout -b test-prometheus-upgrade +$ vim argocd-apps/prometheus.yaml # Bump chart version +$ git commit -am "Test Prometheus 56.0.0" +$ git push origin test-prometheus-upgrade + +# Temporarily point ArgoCD at the feature branch +$ kubectl patch application prometheus -n cicd \ + --type merge \ + -p '{"spec":{"source":{"targetRevision":"test-prometheus-upgrade"}}}' + +# Verify changes in ArgoCD Web UI +# If good: merge to master +# If bad: revert the patch +``` + +## Challenges and Solutions + +### Challenge 1: Helm Release Adoption + +When creating an Application for an existing Helm release, ArgoCD needs to "adopt" the resources. This failed initially with errors like: + +``` +The Helm operation failed with an error: release miniflux failed, and has been uninstalled due to atomic being set: timed out waiting for the condition +``` + +**Solution**: For existing Helm releases, I first ensured the Application manifest matched the current Helm values exactly. ArgoCD then recognized the resources were already in the desired state and adopted them without re-deploying. + +### Challenge 2: Persistent Volumes Not Tracked by Helm + +PersistentVolumes are cluster-scoped resources, not namespace-scoped. Many of my Helm charts created PVs using `kubectl apply -f persistent-volumes.yaml` outside of Helm. + +**Solution**: For simple apps, I moved the PV definitions into the Helm chart templates. For complex apps (like Prometheus), I used the multi-source pattern with PVs in the `manifests/` directory with sync wave 0. + +### Challenge 3: Secrets Management + +ArgoCD stores Application manifests in Git, but secrets shouldn't be committed in plaintext. + +**Solution (current)**: Secrets are created manually with `kubectl create secret` and referenced by the Helm charts. The secrets themselves aren't managed by ArgoCD. + +**Future enhancement**: Migrate to External Secrets Operator (ESO) to manage secrets declaratively while storing the actual secrets in a separate backend (Kubernetes secrets in a separate namespace, or eventually Vault). + +### Challenge 4: Grafana Not Reloading Datasources + +After updating the Grafana datasources ConfigMap, Grafana wouldn't detect the changes until pods were manually deleted. + +**Solution**: Created a PostSync hook that automatically restarts Grafana pods after every ArgoCD sync. This runs as a Kubernetes Job in sync wave 10, ensuring it executes after all other resources are deployed. + +### Challenge 5: Prometheus With Multiple Sources + +Prometheus needed both the upstream Helm chart and custom manifests (recording rules, dashboards, PVs). + +**Solution**: Used ArgoCD's multi-source feature to combine: +* Helm chart from `prometheus-community.github.io/helm-charts` +* Additional manifests from `codeberg.org/snonux/conf.git` at path `f3s/prometheus/manifests` + +This keeps the upstream chart cleanly separated from custom configuration. + +### Challenge 6: Sync Ordering for Prometheus + +Prometheus resources have dependencies: +* PVs before PVCs +* Secrets before Prometheus Operator +* PrometheusRule CRDs before Prometheus Operator can process them +* Grafana must be running before the restart hook executes + +**Solution**: Added sync wave annotations to all resources in `prometheus/manifests/`: +* Wave 0: PVs, RBAC +* Wave 1: Secrets, ConfigMaps +* Wave 3: PrometheusRule CRDs (recording rules) +* Wave 4: Dashboard ConfigMaps +* Wave 10: PostSync hook (Grafana restart) + +ArgoCD deploys resources in wave order, ensuring correct sequencing. + +## Justfile Evolution + +The Justfiles evolved from deployment tools to utility scripts: + +**Before (Helm deployment)**: +```makefile +install: + helm install miniflux ./helm-chart -n services + +upgrade: + helm upgrade miniflux ./helm-chart -n services + +uninstall: + helm uninstall miniflux -n services +``` + +**After (ArgoCD utilities)**: +```makefile +status: + @kubectl get pods -n services -l app=miniflux + @kubectl get application miniflux -n cicd -o jsonpath='Sync: {.status.sync.status}, Health: {.status.health.status}' + +sync: + @kubectl annotate application miniflux -n cicd argocd.argoproj.io/refresh=normal --overwrite + +argocd-status: + argocd app get miniflux --core + +logs: + kubectl logs -n services -l app=miniflux --tail=100 -f +``` + +The Justfiles now provide: +* `status`: Quick health check +* `sync`: Force immediate ArgoCD sync (instead of waiting 3 minutes) +* `argocd-status`: Detailed ArgoCD application status +* `logs`: Tail application logs +* Application-specific utilities (e.g., `port-forward`, `restart`) + +## Lessons Learned + +1. **Incremental migration is safer than big-bang**: Migrating one app at a time allowed me to validate the pattern and fix issues before they affected all apps. + +2. **Start with simple apps**: The first migration (simple services) established the basic pattern. Complex apps (Prometheus) came later after the pattern was proven. + +3. **Sync waves are essential for complex apps**: Without sync waves, resources deployed in random order and caused failures. Proper ordering eliminated all deployment issues. + +4. **Multi-source is powerful**: Combining upstream Helm charts with custom manifests keeps configuration clean and maintainable. + +5. **PostSync hooks replace manual steps**: The Grafana restart hook eliminated a manual step that was easy to forget. + +6. **Documentation in Git is better than tribal knowledge**: The Application manifests document exactly what's deployed and how. No more "let me check my shell history to remember how I deployed this." + +7. **Self-healing prevents configuration drift**: Multiple times I've manually tweaked something for debugging, forgotten about it, and ArgoCD automatically reverted it back to the desired state. + +8. **ArgoCD Web UI is invaluable**: Seeing the resource tree, sync status, and health status at a glance is much better than running multiple `kubectl` commands. + +## Future Improvements + +### 1. External Secrets Operator + +Currently, secrets are manually created with `kubectl create secret`. This works but isn't declarative. Plan: + +* Deploy External Secrets Operator (ESO) +* Store actual secrets in a Kubernetes Secret in a separate `secrets` namespace +* Create ExternalSecret CRDs that reference the backend secrets +* ArgoCD manages the ExternalSecret CRDs, ESO creates the actual Secrets + +This makes secrets declarative while keeping them out of Git. + +### 2. ApplicationSet for Similar Apps + +Many apps have nearly identical Application manifests (miniflux, freshrss, wallabag, etc.). ArgoCD ApplicationSets can generate multiple Applications from a template: + +```yaml +apiVersion: argoproj.io/v1alpha1 +kind: ApplicationSet +metadata: + name: simple-services + namespace: cicd +spec: + generators: + - list: + elements: + - app: miniflux + - app: freshrss + - app: wallabag + template: + metadata: + name: '{{app}}' + spec: + project: default + source: + repoURL: https://codeberg.org/snonux/conf.git + targetRevision: master + path: 'f3s/{{app}}/helm-chart' + destination: + server: https://kubernetes.default.svc + namespace: services + syncPolicy: + automated: + prune: true + selfHeal: true +``` + +One ApplicationSet could replace 10+ individual Application manifests. + +### 3. App-of-Apps Pattern + +Currently, all Application manifests are applied manually with `kubectl apply -f argocd-apps/`. An alternative is the "app-of-apps" pattern: + +Create a root Application that deploys all other Applications: + +```yaml +apiVersion: argoproj.io/v1alpha1 +kind: Application +metadata: + name: root + namespace: cicd +spec: + source: + repoURL: https://codeberg.org/snonux/conf.git + targetRevision: master + path: f3s/argocd-apps + destination: + server: https://kubernetes.default.svc + namespace: cicd + syncPolicy: + automated: + prune: true + selfHeal: true +``` + +Then disaster recovery becomes: +```sh +$ kubectl apply -f root-app.yaml +# Root app deploys all 21 applications automatically +``` + +### 4. ArgoCD Image Updater + +For applications with custom Docker images (like the registry, tracing-demo), ArgoCD Image Updater can automatically update the image tag in Git when a new image is pushed: + +```yaml +metadata: + annotations: + argocd-image-updater.argoproj.io/image-list: | + app=registry.f3s.buetow.org/miniflux:~^v + argocd-image-updater.argoproj.io/write-back-method: git +``` + +When a new image `registry.f3s.buetow.org/miniflux:v2.1.0` is pushed, Image Updater automatically: +1. Updates the Helm values in Git +2. Commits the change +3. ArgoCD syncs the new image + +This creates a fully automated CI/CD pipeline. + +## Summary + +Migrating from imperative Helm deployments to declarative GitOps with ArgoCD transformed how I manage the f3s cluster: + +**Before**: +* Manual Helm commands for every change +* No visibility into cluster state +* Difficult to track what changed and when +* Disaster recovery required rebuilding from memory/notes + +**After**: +* Git is the single source of truth +* Automatic synchronization of changes +* Complete audit trail in Git history +* Drift detection and self-healing +* Disaster recovery: deploy ArgoCD, apply Application manifests, done + +The migration took several days spread over a few weeks, migrating one application at a time. The result is a more maintainable, reliable, and recoverable cluster. + +All 21 applications are now managed via GitOps, with the configuration living in: + +=> https://codeberg.org/snonux/conf/src/branch/master/f3s codeberg.org/snonux/conf/f3s + +ArgoCD has become an essential part of the f3s infrastructure, and I can't imagine managing the cluster without it. + +Other *BSD-related posts: + +<< template::inline::rindex bsd + +E-Mail your comments to `paul@nospam.buetow.org` + +=> ../ Back to the main site |