1. Kubernetes (K8s) — Complete Explanation
Kubernetes (K8s) is an orchestration platform that helps you run and manage containers
at scale. It automates deployment, scaling, load balancing, storage management, and self-healing.
1.1 Kubernetes Architecture (In Simple Terms)
- Master Node – Controls the cluster (API Server, Scheduler, Controller Manager).
- Worker Nodes – Run your application containers.
- Kubelet – Agent on each worker node.
- Kube Proxy – Handles network routing.
- ETCD – Stores cluster state.
1.2 Core Kubernetes Objects
- Pods: Smallest deployable unit containing one or more containers.
- Deployments: Handle updates, scaling, and rollout/rollback.
- Services: Exposes Pods within or outside the cluster.
- Ingress: Provides domain-based routing with HTTPS.
Sample Commands
kubectl get pods
kubectl get deployments
kubectl apply -f deployment.yml
kubectl describe pod myapp-pod
1.3 Helm Charts
Helm is a package manager for Kubernetes. It bundles YAML files and simplifies deployments.
- Reusable templates
- Version-controlled application releases
- Easy upgrades & rollbacks
1.4 Stateful Workloads
Used for apps like databases that require persistent storage.
- StatefulSets
- Persistent Volumes (PV)
- Persistent Volume Claims (PVC)
2. AWS Cloud — Foundational + Practical Knowledge
AWS (Amazon Web Services) is the world’s leading cloud platform. In DevOps, AWS is commonly used
for hosting apps, CI/CD pipelines, monitoring, databases, virtual machines, etc.
2.1 AWS EC2 (Virtual Servers)
- Create, configure, and manage Linux/Windows servers.
- Learn SSH, key pairs, and security groups.
- Understand AMIs and Instance Types.
2.2 AWS S3 (Storage Service)
- Highly durable object storage.
- Used for website hosting, backup, logs, CI/CD storage.
- Understand buckets, policies, presigned URLs.
2.3 AWS IAM (Identity & Access Management)
- Users, groups, roles, and permissions.
- Security best practices (MFA, least privilege).
2.4 AWS VPC (Networking)
- Subnets, Route Tables, Gateways.
- Public vs Private Subnets.
- NAT Gateway for secure internet access.
2.5 AWS RDS (Managed Database Service)
- MySQL, PostgreSQL, MariaDB, SQL Server.
- Automated backups, failover, scaling.
3. Monitoring — Complete Observability Stack
3.1 Prometheus
- Time-series metrics scraper.
- Kubernetes-native monitoring.
- Pull-based architecture.
3.2 Grafana
- Dashboard visualization tool.
- Connects with Prometheus, Loki, Elastic, MySQL, etc.
3.3 ELK / EFK Stack
Elasticsearch + Logstash (or Fluentd) + Kibana.
- Used for log aggregation and analytics.
- Essential for tracking errors & app activity.