Module Review: Production Patterns
You’ve learned how to package applications, automate operations, monitor performance, centralize logs, and implement GitOps.
1. Key Takeaways
- Helm is the package manager for Kubernetes. Use Templates and Values to manage configuration across environments (Dev/Stage/Prod) and stop YAML sprawl.
- Operators extend Kubernetes with Custom Resource Definitions (CRDs) and Controllers to automate complex operational tasks (e.g., database failover).
- Prometheus uses a Pull Model to scrape metrics. Use PromQL to query dimensional data and AlertManager for notifications.
- EFK Stack (Elasticsearch, Fluentd, Kibana) centralizes logs. Use Structured Logging (JSON) to make logs queryable.
- GitOps (ArgoCD) treats Git as the single source of truth. An agent in the cluster continuously syncs the state to match the Git repository.
2. Interactive Flashcards
What is the main difference between Helm v2 and v3?
Helm v3 removed Tiller (the server-side component), improving security by using standard Kubernetes RBAC.
What is the "Reconciliation Loop"?
The process where a Controller continuously observes the Current State, compares it to the Desired State, and acts to fix any drift.
Why does Prometheus use a Pull model?
To prevent applications from overwhelming the monitoring server (DDoS) and to simplify service discovery.
What is Structured Logging?
Logging in a machine-readable format like JSON instead of plain text, allowing for efficient filtering and aggregation.
What is Drift Detection in GitOps?
The ability of the GitOps agent (ArgoCD) to notice when the cluster state differs from the Git repository (e.g., manual kubectl edits).
What is a Sidecar in the context of logging?
A container running alongside the main app container in the same Pod, used to ship logs (e.g., forwarding log files to stdout).
3. Cheat Sheet
| Concept | Tool | Key Command / Term |
|---|---|---|
| Packaging | Helm | helm install my-release ./chart |
| Automation | Operator SDK | Reconcile(req) |
| Monitoring | Prometheus | rate(http_requests_total[5m]) |
| Logging | Fluentd | DaemonSet |
| CD | ArgoCD | Application (CRD) |
| Progressive | Argo Rollouts | Canary strategy |
4. Next Steps
Now that you have mastered production patterns, you are ready to secure your cluster.
Proceed to Module 09: Security (Coming Soon).