kubernetes-orchestration

name	kubernetes-orchestration
description	Kubernetes container orchestration. Use when deploying to Kubernetes, writing manifests, configuring Helm charts, or troubleshooting cluster issues.

Kubernetes Orchestration

Comprehensive guide for deploying, managing, and scaling applications on Kubernetes.

When to Use

• Deploying applications to Kubernetes
• Writing and reviewing Kubernetes manifests
• Creating Helm charts
• Configuring ingress and networking
• Setting up autoscaling
• Troubleshooting pod and cluster issues

Core Concepts

Resource Hierarchy

Cluster
├── Namespaces
│   ├── Deployments → ReplicaSets → Pods → Containers
│   ├── StatefulSets → Pods
│   ├── DaemonSets → Pods
│   ├── Services (ClusterIP, NodePort, LoadBalancer)
│   ├── Ingress
│   ├── ConfigMaps
│   ├── Secrets
│   ├── PersistentVolumeClaims
│   └── ServiceAccounts
└── Cluster-wide
    ├── Nodes
    ├── PersistentVolumes
    ├── StorageClasses
    ├── ClusterRoles
    └── CustomResourceDefinitions

Namespace Organization

# namespace.yaml
apiVersion: v1
kind: Namespace
metadata:
  name: myapp-production
  labels:
    name: myapp-production
    environment: production
    team: platform

Namespace Strategy:

namespaces/
├── production
├── staging
├── development
├── monitoring       # Prometheus, Grafana
├── logging          # ELK, Loki
├── ingress-nginx    # Ingress controllers
└── cert-manager     # TLS certificates

Deployments

Production-Ready Deployment:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
  namespace: production
  labels:
    app: myapp
    version: v1.0.0
spec:
  replicas: 3
  revisionHistoryLimit: 5
  strategy:
    type: RollingUpdate
    rollingUpdate:
      maxSurge: 1
      maxUnavailable: 0
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
        version: v1.0.0
      annotations:
        prometheus.io/scrape: "true"
        prometheus.io/port: "9090"
    spec:
      serviceAccountName: myapp
      securityContext:
        runAsNonRoot: true
        runAsUser: 1000
        fsGroup: 1000

      containers:
        - name: myapp
          image: registry.example.com/myapp:v1.0.0
          imagePullPolicy: IfNotPresent

          ports:
            - name: http
              containerPort: 8080
              protocol: TCP
            - name: metrics
              containerPort: 9090
              protocol: TCP

          env:
            - name: NODE_ENV
              value: "production"
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: DATABASE_URL
              valueFrom:
                secretKeyRef:
                  name: myapp-secrets
                  key: database-url

          envFrom:
            - configMapRef:
                name: myapp-config

          resources:
            requests:
              cpu: 100m
              memory: 128Mi
            limits:
              cpu: 500m
              memory: 512Mi

          livenessProbe:
            httpGet:
              path: /health/live
              port: http
            initialDelaySeconds: 30
            periodSeconds: 10
            timeoutSeconds: 5
            failureThreshold: 3

          readinessProbe:
            httpGet:
              path: /health/ready
              port: http
            initialDelaySeconds: 5
            periodSeconds: 5
            timeoutSeconds: 3
            failureThreshold: 3

          startupProbe:
            httpGet:
              path: /health/live
              port: http
            initialDelaySeconds: 10
            periodSeconds: 5
            failureThreshold: 30

          securityContext:
            allowPrivilegeEscalation: false
            readOnlyRootFilesystem: true
            capabilities:
              drop:
                - ALL

          volumeMounts:
            - name: tmp
              mountPath: /tmp
            - name: config
              mountPath: /app/config
              readOnly: true

      volumes:
        - name: tmp
          emptyDir: {}
        - name: config
          configMap:
            name: myapp-config

      affinity:
        podAntiAffinity:
          preferredDuringSchedulingIgnoredDuringExecution:
            - weight: 100
              podAffinityTerm:
                labelSelector:
                  matchLabels:
                    app: myapp
                topologyKey: kubernetes.io/hostname

      topologySpreadConstraints:
        - maxSkew: 1
          topologyKey: topology.kubernetes.io/zone
          whenUnsatisfiable: ScheduleAnyway
          labelSelector:
            matchLabels:
              app: myapp

      terminationGracePeriodSeconds: 30

Services

ClusterIP (Internal):

apiVersion: v1
kind: Service
metadata:
  name: myapp
  namespace: production
spec:
  type: ClusterIP
  selector:
    app: myapp
  ports:
    - name: http
      port: 80
      targetPort: http
      protocol: TCP

LoadBalancer (External):

apiVersion: v1
kind: Service
metadata:
  name: myapp-lb
  namespace: production
  annotations:
    # AWS NLB
    service.beta.kubernetes.io/aws-load-balancer-type: nlb
    service.beta.kubernetes.io/aws-load-balancer-internal: "false"
spec:
  type: LoadBalancer
  selector:
    app: myapp
  ports:
    - name: http
      port: 80
      targetPort: http
    - name: https
      port: 443
      targetPort: https

Headless Service (StatefulSets):

apiVersion: v1
kind: Service
metadata:
  name: myapp-headless
spec:
  type: ClusterIP
  clusterIP: None
  selector:
    app: myapp
  ports:
    - port: 80

Ingress

Nginx Ingress:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: myapp-ingress
  namespace: production
  annotations:
    kubernetes.io/ingress.class: nginx
    nginx.ingress.kubernetes.io/ssl-redirect: "true"
    nginx.ingress.kubernetes.io/proxy-body-size: "50m"
    cert-manager.io/cluster-issuer: letsencrypt-prod
spec:
  tls:
    - hosts:
        - myapp.example.com
        - api.example.com
      secretName: myapp-tls
  rules:
    - host: myapp.example.com
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: myapp-frontend
                port:
                  number: 80
    - host: api.example.com
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: myapp-api
                port:
                  number: 80

ConfigMaps & Secrets

ConfigMap:

apiVersion: v1
kind: ConfigMap
metadata:
  name: myapp-config
  namespace: production
data:
  # Simple key-value
  LOG_LEVEL: "info"
  API_TIMEOUT: "30s"

  # File content
  config.yaml: |
    server:
      port: 8080
      host: 0.0.0.0
    features:
      cache: true
      debug: false

Secrets:

apiVersion: v1
kind: Secret
metadata:
  name: myapp-secrets
  namespace: production
type: Opaque
data:
  # Base64 encoded
  database-url: cG9zdGdyZXM6Ly91c2VyOnBhc3NAZGIvYXBw
  api-key: c2VjcmV0LWFwaS1rZXk=
stringData:
  # Plain text (will be encoded)
  another-secret: "plain-text-value"

External Secrets (with External Secrets Operator):

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: myapp-secrets
spec:
  refreshInterval: 1h
  secretStoreRef:
    kind: ClusterSecretStore
    name: aws-secrets-manager
  target:
    name: myapp-secrets
    creationPolicy: Owner
  data:
    - secretKey: database-url
      remoteRef:
        key: prod/myapp/database
        property: url

StatefulSets

Database StatefulSet:

apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: postgresql
  namespace: production
spec:
  serviceName: postgresql-headless
  replicas: 3
  selector:
    matchLabels:
      app: postgresql
  template:
    metadata:
      labels:
        app: postgresql
    spec:
      containers:
        - name: postgresql
          image: postgres:16-alpine
          ports:
            - containerPort: 5432
          env:
            - name: POSTGRES_PASSWORD
              valueFrom:
                secretKeyRef:
                  name: postgresql-secrets
                  key: password
            - name: PGDATA
              value: /var/lib/postgresql/data/pgdata
          volumeMounts:
            - name: data
              mountPath: /var/lib/postgresql/data
          resources:
            requests:
              cpu: 250m
              memory: 256Mi
            limits:
              cpu: 1000m
              memory: 1Gi
  volumeClaimTemplates:
    - metadata:
        name: data
      spec:
        accessModes: ["ReadWriteOnce"]
        storageClassName: fast-ssd
        resources:
          requests:
            storage: 10Gi

Autoscaling

Horizontal Pod Autoscaler:

apiVersion: autoscaling/v2
kind: HorizontalPodAutoscaler
metadata:
  name: myapp-hpa
  namespace: production
spec:
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: myapp
  minReplicas: 3
  maxReplicas: 20
  metrics:
    - type: Resource
      resource:
        name: cpu
        target:
          type: Utilization
          averageUtilization: 70
    - type: Resource
      resource:
        name: memory
        target:
          type: Utilization
          averageUtilization: 80
    - type: Pods
      pods:
        metric:
          name: http_requests_per_second
        target:
          type: AverageValue
          averageValue: 1000
  behavior:
    scaleDown:
      stabilizationWindowSeconds: 300
      policies:
        - type: Percent
          value: 10
          periodSeconds: 60
    scaleUp:
      stabilizationWindowSeconds: 0
      policies:
        - type: Percent
          value: 100
          periodSeconds: 15
        - type: Pods
          value: 4
          periodSeconds: 15
      selectPolicy: Max

Vertical Pod Autoscaler:

apiVersion: autoscaling.k8s.io/v1
kind: VerticalPodAutoscaler
metadata:
  name: myapp-vpa
spec:
  targetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: myapp
  updatePolicy:
    updateMode: Auto
  resourcePolicy:
    containerPolicies:
      - containerName: myapp
        minAllowed:
          cpu: 100m
          memory: 128Mi
        maxAllowed:
          cpu: 2
          memory: 2Gi

RBAC

ServiceAccount:

apiVersion: v1
kind: ServiceAccount
metadata:
  name: myapp
  namespace: production
---
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
  name: myapp-role
  namespace: production
rules:
  - apiGroups: [""]
    resources: ["configmaps", "secrets"]
    verbs: ["get", "list", "watch"]
  - apiGroups: [""]
    resources: ["pods"]
    verbs: ["get", "list"]
---
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
  name: myapp-rolebinding
  namespace: production
subjects:
  - kind: ServiceAccount
    name: myapp
    namespace: production
roleRef:
  kind: Role
  name: myapp-role
  apiGroup: rbac.authorization.k8s.io

Network Policies

Restrict Ingress/Egress:

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: myapp-network-policy
  namespace: production
spec:
  podSelector:
    matchLabels:
      app: myapp
  policyTypes:
    - Ingress
    - Egress
  ingress:
    - from:
        - namespaceSelector:
            matchLabels:
              name: ingress-nginx
        - podSelector:
            matchLabels:
              app: myapp-frontend
      ports:
        - protocol: TCP
          port: 8080
  egress:
    - to:
        - podSelector:
            matchLabels:
              app: postgresql
      ports:
        - protocol: TCP
          port: 5432
    - to:
        - namespaceSelector: {}
          podSelector:
            matchLabels:
              k8s-app: kube-dns
      ports:
        - protocol: UDP
          port: 53

Helm Charts

Chart Structure:

myapp-chart/
├── Chart.yaml
├── values.yaml
├── values-production.yaml
├── templates/
│   ├── _helpers.tpl
│   ├── deployment.yaml
│   ├── service.yaml
│   ├── ingress.yaml
│   ├── configmap.yaml
│   ├── secrets.yaml
│   ├── hpa.yaml
│   └── NOTES.txt
└── charts/           # Dependencies

Chart.yaml:

apiVersion: v2
name: myapp
description: My Application Helm Chart
type: application
version: 1.0.0
appVersion: "1.0.0"

dependencies:
  - name: postgresql
    version: 12.x.x
    repository: https://charts.bitnami.com/bitnami
    condition: postgresql.enabled

values.yaml:

replicaCount: 3

image:
  repository: registry.example.com/myapp
  tag: latest
  pullPolicy: IfNotPresent

service:
  type: ClusterIP
  port: 80

ingress:
  enabled: true
  className: nginx
  hosts:
    - host: myapp.example.com
      paths:
        - path: /
          pathType: Prefix
  tls:
    - secretName: myapp-tls
      hosts:
        - myapp.example.com

resources:
  requests:
    cpu: 100m
    memory: 128Mi
  limits:
    cpu: 500m
    memory: 512Mi

autoscaling:
  enabled: true
  minReplicas: 3
  maxReplicas: 20
  targetCPUUtilizationPercentage: 70

postgresql:
  enabled: true
  auth:
    database: myapp

Template Example:

# templates/deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: {{ include "myapp.fullname" . }}
  labels:
    {{- include "myapp.labels" . | nindent 4 }}
spec:
  {{- if not .Values.autoscaling.enabled }}
  replicas: {{ .Values.replicaCount }}
  {{- end }}
  selector:
    matchLabels:
      {{- include "myapp.selectorLabels" . | nindent 6 }}
  template:
    metadata:
      labels:
        {{- include "myapp.selectorLabels" . | nindent 8 }}
    spec:
      containers:
        - name: {{ .Chart.Name }}
          image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
          ports:
            - containerPort: 8080
          resources:
            {{- toYaml .Values.resources | nindent 12 }}

Commands Reference

# Cluster info
kubectl cluster-info
kubectl get nodes
kubectl top nodes

# Namespace operations
kubectl get namespaces
kubectl create namespace myapp
kubectl config set-context --current --namespace=myapp

# Workloads
kubectl get pods -o wide
kubectl get deployments
kubectl describe pod <pod-name>
kubectl logs <pod-name> -f
kubectl logs <pod-name> -c <container-name>
kubectl exec -it <pod-name> -- /bin/sh

# Apply manifests
kubectl apply -f manifest.yaml
kubectl apply -f ./manifests/
kubectl apply -k ./kustomize/  # Kustomize

# Scaling
kubectl scale deployment myapp --replicas=5
kubectl autoscale deployment myapp --min=3 --max=10 --cpu-percent=70

# Rolling updates
kubectl set image deployment/myapp myapp=myapp:v2
kubectl rollout status deployment/myapp
kubectl rollout history deployment/myapp
kubectl rollout undo deployment/myapp
kubectl rollout undo deployment/myapp --to-revision=2

# Debug
kubectl describe pod <pod-name>
kubectl get events --sort-by=.metadata.creationTimestamp
kubectl run debug --rm -it --image=busybox -- /bin/sh
kubectl port-forward pod/<pod-name> 8080:8080
kubectl cp <pod-name>:/path/to/file ./local-file

# Helm
helm install myapp ./myapp-chart
helm upgrade myapp ./myapp-chart -f values-prod.yaml
helm rollback myapp 1
helm list
helm uninstall myapp

Troubleshooting

Issue	Debug Command
Pod stuck Pending	kubectl describe pod <name> - check events
Pod CrashLoopBackOff	kubectl logs <pod> --previous
Service not reachable	kubectl get endpoints <service>
Ingress not working	Check ingress controller logs
Node pressure	kubectl describe node <name>
OOMKilled	Increase memory limits

Common Pod States:

Pending      → Check node resources, PVC binding
ContainerCreating → Image pull, volume mount
Running      → Healthy
Succeeded    → Job completed
Failed       → Check logs
Unknown      → Node communication issue

Checklist

Before deploying:

• Resource requests/limits defined
• Liveness and readiness probes configured
• Security context (non-root, read-only fs)
• ConfigMaps/Secrets externalized
• Network policies in place
• HPA configured for scaling
• Pod disruption budgets set
• Affinity/anti-affinity rules
• Image tags pinned (not :latest)

Integration

Works with:

• /devops - Deployment pipelines
• /docker - Container images for K8s
• gitops skill - ArgoCD/Flux deployments
• /aws, /gcp, /azure - Managed K8s services
• /security - Cluster security review