How to deploy a Kubernetes service using NodePort on Amazon AWS? - amazon-web-services

Question

I have created a cluster on AWS EC2 using kops consisting of a master node and two worker nodes, all with public IPv4 assigned.
Now, I want to create a deployment with a service using NodePort to expose the application to the public.
After having created the service, I retrieve the following information, showing that it correctly identified my three pods:
nlykkei:~/projects/k8s-examples$ kubectl describe svc hello-svc
Name: hello-svc
Namespace: default
Labels: app=hello
Annotations: kubectl.kubernetes.io/last-applied-configuration:
{"apiVersion":"v1","kind":"Service","metadata":{"annotations":{},"labels":{"app":"hello"},"name":"hello-svc","namespace":"default"},"spec"...
Selector: app=hello-world
Type: NodePort
IP: 100.69.62.27
Port: <unset> 8080/TCP
TargetPort: 8080/TCP
NodePort: <unset> 30001/TCP
Endpoints: 100.96.1.5:8080,100.96.2.3:8080,100.96.2.4:8080
Session Affinity: None
External Traffic Policy: Cluster
Events: <none>
However, when I try to visit any of my public IPv4's on port 30001, I get no response from the server. I have already created a Security Group allowing all ingress traffic to port 30001 for all of the instances.
Everything works with Docker Desktop for Mac, and here I notice the following service field not present in the output above:
LoadBalancer Ingress: localhost
I've already studied https://kubernetes.io/docs/concepts/services-networking/service/, and think that NodePort should serve my needs?
Any help is appreciated!

Answer 1

So you want to have a service able to be accessed from public. In order to achieve this I would recommend to create a ClusterIP service and then an Ingress for that service. So, saying that you have the deployment hello-world serving at 8081 you will then have the following two objects:
Service:
apiVersion: v1
kind: Service
metadata:
name: hello-world
labels:
app: hello-world
spec:
ports:
- name: service
port: 8081(or whatever you want)
protocol: TCP
targetPort: 8080 (here goes the opened port in your pods)
selector:
app: hello-world
type: ClusterIP
Ingress:
apiVersion: networking.k8s.io/v1beta1
kind: Ingress
metadata:
labels:
app: hello-world
name: hello-world
spec:
rules:
- host: hello-world.mycutedomainname.com
http:
paths:
- backend:
serviceName: hello-world
servicePort: 8081 (or whatever you have set for the service port)
path: /
Note: the name tag in the service's port is optional.