Creating Kubernetes Deployments

Generate production-ready Kubernetes manifests with health checks, resource limits, and security best practices.

Quick Start

Basic Deployment + Service

deployment.yaml

apiVersion: apps/v1 kind: Deployment metadata: name: my-api labels: app: my-api spec: replicas: 3 selector: matchLabels: app: my-api strategy: type: RollingUpdate rollingUpdate: maxSurge: 25% maxUnavailable: 25% template: metadata: labels: app: my-api spec: containers: - name: my-api image: my-registry/my-api:v1.0.0 ports: - containerPort: 8080 # 8080: HTTP proxy port resources: requests: cpu: 100m memory: 256Mi limits: cpu: 500m memory: 512Mi livenessProbe: httpGet: path: /healthz port: 8080 # HTTP proxy port initialDelaySeconds: 30 periodSeconds: 10 readinessProbe: httpGet: path: /readyz port: 8080 # HTTP proxy port initialDelaySeconds: 5 periodSeconds: 5

apiVersion: v1 kind: Service metadata: name: my-api spec: type: ClusterIP selector: app: my-api ports:

• port: 80 targetPort: 8080 # HTTP proxy port

Deployment Strategies

Strategy Use Case Configuration

RollingUpdate Zero-downtime updates maxSurge: 25% , maxUnavailable: 25%

Recreate Stateful apps, incompatible versions type: Recreate

Blue-Green Instant rollback Two deployments, switch Service selector

Canary Gradual rollout Multiple deployments with weighted traffic

Blue-Green Deployment

Blue deployment (current production)

apiVersion: apps/v1 kind: Deployment metadata: name: my-api-blue labels: app: my-api version: blue spec: replicas: 3 selector: matchLabels: app: my-api version: blue template: metadata: labels: app: my-api version: blue spec: containers: - name: my-api image: my-registry/my-api:v1.0.0

Service points to blue

apiVersion: v1 kind: Service metadata: name: my-api spec: selector: app: my-api version: blue # Switch to 'green' for deployment ports:

• port: 80 targetPort: 8080 # 8080: HTTP proxy port

Service Types

Type Use Case Access

ClusterIP Internal services my-api.namespace.svc.cluster.local

NodePort Development, debugging <NodeIP>:<NodePort>

LoadBalancer External traffic (cloud) Cloud provider LB IP

ExternalName External service proxy DNS CNAME

Ingress with TLS

apiVersion: networking.k8s.io/v1 kind: Ingress metadata: name: my-api-ingress annotations: cert-manager.io/cluster-issuer: letsencrypt-prod nginx.ingress.kubernetes.io/ssl-redirect: "true" spec: ingressClassName: nginx tls:

• hosts:
  • api.example.com secretName: api-tls-secret rules:
• host: api.example.com http: paths:
  • path: / pathType: Prefix backend: service: name: my-api port: number: 80

Resource Limits

Always set resource requests and limits:

resources: requests: # Guaranteed resources cpu: 100m # 0.1 CPU core memory: 256Mi limits: # Maximum allowed cpu: 500m # 0.5 CPU core memory: 512Mi

Workload Type CPU Request Memory Request CPU Limit Memory Limit

Web API 100m-500m 256Mi-512Mi 500m-1000m 512Mi-1Gi

Worker 250m-1000m 512Mi-1Gi 1000m-2000m 1Gi-2Gi

Database 500m-2000m 1Gi-4Gi 2000m-4000m 4Gi-8Gi

Health Checks

Liveness Probe (Is container running?)

livenessProbe: httpGet: path: /healthz port: 8080 # 8080: HTTP proxy port initialDelaySeconds: 30 # Wait for app startup periodSeconds: 10 # Check every 10s timeoutSeconds: 5 # Timeout per check failureThreshold: 3 # Restart after 3 failures

Readiness Probe (Ready for traffic?)

readinessProbe: httpGet: path: /readyz port: 8080 # 8080: HTTP proxy port initialDelaySeconds: 5 # Quick check after start periodSeconds: 5 # Check every 5s successThreshold: 1 # 1 success = ready failureThreshold: 3 # Remove from LB after 3 failures

Startup Probe (Slow-starting apps)

startupProbe: httpGet: path: /healthz port: 8080 # 8080: HTTP proxy port initialDelaySeconds: 0 periodSeconds: 10 failureThreshold: 30 # Allow 5 minutes to start (30 * 10s)

Horizontal Pod Autoscaler

apiVersion: autoscaling/v2 kind: HorizontalPodAutoscaler metadata: name: my-api-hpa spec: scaleTargetRef: apiVersion: apps/v1 kind: Deployment name: my-api minReplicas: 2 maxReplicas: 10 metrics:

• type: Resource resource: name: cpu target: type: Utilization averageUtilization: 70
• type: Resource resource: name: memory target: type: Utilization averageUtilization: 80 behavior: scaleDown: stabilizationWindowSeconds: 300 # 300: Wait 5min before scale down

ConfigMaps and Secrets

ConfigMap (Non-sensitive config)

apiVersion: v1 kind: ConfigMap metadata: name: my-api-config data: LOG_LEVEL: "info" API_ENDPOINT: "https://api.example.com" config.yaml: | server: port: 8080 # 8080: HTTP proxy port features: enabled: true

Secret (Sensitive data - base64 encoded)

apiVersion: v1 kind: Secret metadata: name: my-api-secrets type: Opaque data: API_KEY: YXBpLWtleS1oZXJl # echo -n "api-key-here" | base64 DATABASE_URL: cG9zdGdyZXM6Ly8uLi4= # echo -n "postgres://..." | base64

Using in Deployment

spec: containers:

• name: my-api envFrom:
  • configMapRef: name: my-api-config
  • secretRef: name: my-api-secrets volumeMounts:
  • name: config-volume mountPath: /app/config volumes:
• name: config-volume configMap: name: my-api-config

Instructions

Gather Requirements

• Application name, container image, port

• Replica count and resource requirements

• Health check endpoints

• External access requirements (Ingress/LoadBalancer)

Generate Base Manifests

• Create Deployment with resource limits and probes

• Create Service (ClusterIP for internal, LoadBalancer for external)

• Add ConfigMap for configuration

• Add Secret for sensitive data

Add Production Features

• Configure Ingress with TLS if external access needed

• Add HPA for auto-scaling

• Add NetworkPolicy for security

• Add PodDisruptionBudget for availability

Validate and Apply

Validate manifests

kubectl apply -f manifests/ --dry-run=server

Apply to cluster

kubectl apply -f manifests/

Watch rollout

kubectl rollout status deployment/my-api

Error Handling

See ${CLAUDE_SKILL_DIR}/references/errors.md for comprehensive troubleshooting.

Error Quick Fix

ImagePullBackOff Check image name, tag, registry credentials

CrashLoopBackOff Check logs: kubectl logs <pod>

OOMKilled Increase memory limits

Pending Check resources: kubectl describe pod <pod>

Examples

See ${CLAUDE_SKILL_DIR}/references/examples.md for detailed walkthroughs.

Resources

• Kubernetes documentation: https://kubernetes.io/docs/

• kubectl reference: https://kubernetes.io/docs/reference/kubectl/

• Templates in ${CLAUDE_SKILL_DIR}/assets/

• Scripts in ${CLAUDE_SKILL_DIR}/scripts/

Overview

Deploy applications to Kubernetes with production-ready manifests.

Prerequisites

• Access to the Kubernetes environment or API

• Required CLI tools installed and authenticated

• Familiarity with Kubernetes concepts and terminology

Output

• Configuration files or code changes applied to the project

• Validation report confirming correct implementation

• Summary of changes made and their rationale

See Kubernetes implementation details for output format specifications.