Managed K8s Basics

This page is a hands-on intro to running workloads on a managed cluster, covering the commands and manifests you touch on day one across EKS, GKE, and AKS.

Prerequisites

• kubectl matching your cluster minor (target Kubernetes 1.36; the client may skew one minor).
• Helm 3 for chart-based installs.
• A managed cluster on one of EKS, GKE, or AKS, plus the matching cloud CLI (aws, gcloud, or az).
• Docker Engine 29.6.1 locally only for building images; nodes run containerd via CRI.

Quick install of kubectl and Helm on Debian or Ubuntu:

curl -LO "https://dl.k8s.io/release/v1.36.2/bin/linux/amd64/kubectl"
sudo install -m 0755 kubectl /usr/local/bin/kubectl
curl -fsSL https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

Basic Examples

1. Get cluster credentials

Each cloud writes a kubeconfig entry with its own CLI so kubectl can reach the managed API server.

aws eks update-kubeconfig --name prod --region us-east-1
gcloud container clusters get-credentials prod --region us-central1
az aks get-credentials --resource-group rg-prod --name prod

• Only one of these applies to your cluster; they all merge into ~/.kube/config.
• The token is short-lived and refreshed by the cloud CLI on each call.
• Switch clusters with kubectl config use-context <name>.
• Cloud IAM authenticates you; Kubernetes RBAC still authorizes actions.

2. Inspect the control plane and nodes

Confirm the managed control-plane version and see your worker nodes.

kubectl version --output=yaml
kubectl get nodes -o wide

• The server version is the managed control plane you selected.
• -o wide shows the container runtime column, which reads containerd://....
• Node AGE and VERSION reveal node-pool upgrade drift.
• Nodes stay on their pool version until you upgrade them.

3. Create a namespace

Namespaces are your first isolation boundary for teams and environments.

kubectl create namespace payments
kubectl label namespace payments team=payments

• Namespaces scope names, quotas, RBAC, and NetworkPolicy.
• Labels drive selectors and policy targeting later.
• Delete a namespace to garbage-collect everything inside it.

4. Deploy a workload

A minimal Deployment runs your image with a pinned, non-root container.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web
  namespace: payments
spec:
  replicas: 3
  selector:
    matchLabels: { app: web }
  template:
    metadata:
      labels: { app: web }
    spec:
      containers:
        - name: web
          image: ghcr.io/acme/web@sha256:abc123
          ports:
            - containerPort: 8080

• replicas: 3 spreads pods for availability.
• Pinning by digest (@sha256:...) makes rollouts reproducible.
• The selector must match the pod template labels.
• Apply it with kubectl apply -f web.yaml.

5. Expose the workload

A Service gives pods a stable virtual IP and DNS name inside the cluster.

apiVersion: v1
kind: Service
metadata:
  name: web
  namespace: payments
spec:
  selector: { app: web }
  ports:
    - port: 80
      targetPort: 8080

• The Service load-balances across all matching pod IPs.
• In-cluster DNS resolves web.payments.svc.cluster.local.
• Use type: LoadBalancer to provision a cloud load balancer.
• kube-proxy or the CNI programs the routing on each node.

6. Add health probes

Probes let Kubernetes restart hung pods and hold traffic until ready.

readinessProbe:
  httpGet: { path: /healthz, port: 8080 }
  periodSeconds: 5
livenessProbe:
  httpGet: { path: /livez, port: 8080 }
  periodSeconds: 10

• Readiness gates whether the pod receives Service traffic.
• Liveness restarts a pod that is alive but stuck.
• Keep probe endpoints cheap and dependency-free.
• Missing readiness probes cause traffic to 503 during rollouts.

7. Set requests and limits

Requests drive scheduling and autoscaling; limits cap runaway pods.

resources:
  requests: { cpu: "100m", memory: "128Mi" }
  limits: { cpu: "500m", memory: "256Mi" }

• The scheduler places pods using requests, not limits.
• Exceeding a memory limit gets the container OOMKilled.
• Node autoscalers size nodes from summed requests.
• Serverless modes (Fargate, Autopilot) bill on requests directly.

Intermediate Examples

8. Wire cloud identity to a ServiceAccount

Each cloud federates pod identity so you avoid long-lived secrets.

apiVersion: v1
kind: ServiceAccount
metadata:
  name: web
  namespace: payments
  annotations:
    # EKS IRSA (or use EKS Pod Identity associations instead)
    eks.amazonaws.com/role-arn: arn:aws:iam::111122223333:role/web
    # GKE Workload Identity
    iam.gke.io/gcp-service-account: web@project.iam.gserviceaccount.com

• Annotate the ServiceAccount, then reference it in the pod spec.
• AKS uses Microsoft Entra Workload ID with a federated credential.
• The pod receives a projected token exchanged for cloud credentials.
• Scope the mapped IAM role to least privilege.

9. Enforce a default-deny NetworkPolicy

Pod traffic is open by default; lock it down per namespace.

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: default-deny
  namespace: payments
spec:
  podSelector: {}
  policyTypes: [Ingress, Egress]

• An empty podSelector selects every pod in the namespace.
• With no rules, all ingress and egress are denied.
• Add explicit allow policies for the traffic you need.
• The CNI must support NetworkPolicy for this to take effect.

10. Autoscale on CPU

The HorizontalPodAutoscaler scales replicas from live metrics.

kubectl autoscale deployment web -n payments \
  --cpu-percent=70 --min=3 --max=20

• Requires metrics-server (managed as an add-on on most clouds).
• The HPA scales pods; a node autoscaler then adds nodes.
• Target utilization is a percentage of the CPU request.
• Pair with a PodDisruptionBudget to protect availability.

Stack versions: This page was written for Kubernetes 1.36.2, Docker Engine 29.6.1 (BuildKit default), containerd (CRI runtime on nodes), Helm 3, Compose v2, Argo CD (latest - verify at build), and Gateway API (GA - verify controller support at build).

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