Kubernetes deploy nginx example - unix1998/technical_notes GitHub Wiki

In Kubernetes, deploying an NGINX application typically involves several steps, each defined in a separate YAML file. However, for simplicity, you can also combine multiple configurations into a single YAML file. Here are the essential components you typically need:

1. Namespace (optional): Define a namespace to isolate your application resources.
2. Deployment: Define the deployment configuration for the NGINX pods.
3. Service: Define a service to expose the NGINX deployment within the cluster.
4. Ingress (optional): Define an ingress resource to expose the NGINX service externally.

You can either use separate YAML files for each component or combine them into a single YAML file. Here’s how you can do it in either case:

Separate YAML Files

1. Namespace (optional)

# namespace.yaml
apiVersion: v1
kind: Namespace
metadata:
  name: my-namespace

2. Deployment

# deployment.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  namespace: my-namespace
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80

3. Service

# service.yaml
apiVersion: v1
kind: Service
metadata:
  name: nginx-service
  namespace: my-namespace
spec:
  selector:
    app: nginx
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
  type: ClusterIP

4. Ingress (optional)

# ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-ingress
  namespace: my-namespace
spec:
  rules:
  - host: my-nginx.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: nginx-service
            port:
              number: 80

Combined YAML File

You can also combine the above configurations into a single YAML file.

# combined.yaml
---
apiVersion: v1
kind: Namespace
metadata:
  name: my-namespace
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  namespace: my-namespace
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-service
  namespace: my-namespace
spec:
  selector:
    app: nginx
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
  type: ClusterIP
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-ingress
  namespace: my-namespace
spec:
  rules:
  - host: my-nginx.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: nginx-service
            port:
              number: 80

Applying the Configuration

To apply these configurations, you can use the kubectl apply command.

Separate YAML Files

kubectl apply -f namespace.yaml
kubectl apply -f deployment.yaml
kubectl apply -f service.yaml
kubectl apply -f ingress.yaml

Combined YAML File

kubectl apply -f combined.yaml

By following these steps, you can deploy an NGINX application in Kubernetes with either separate or combined YAML files, depending on your preference.