Newbie question on load balancer

[Sampozzo]

Hello, thank you for this great tool!
I'm studying those days kubernetes and found this great tool, but i'm a little confused about the load balancer, sorry if i ask a so simple question, i hope you can understand.

I'm running this really simple test.yaml, it works but it start a new load balancer only for it. By what i understand, i can use the already available LB, but i can't understand how.
Can you please help me?

---
apiVersion: v1
kind: Namespace
metadata:
  name: test-namespace
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
  namespace: test-namespace
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80
---
kind: Service
apiVersion: v1
metadata:
  labels:
    name: test-lb
  name: test-lb
  namespace: test-namespace
spec:
  type: LoadBalancer
  selector:
    app: nginx
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80 

Thank you very much and sorry!

[mysticaltech]

@Sampozzo You do not need to create a new LB service as you did above. Just use a ClusterIP service, and create an Ingress definition to point to it. That way it will use the LB that is already deployed and connected to your ingress controller, either nginx or traefik.

Btw, I highly recommend your ask chat.openai.com for help on this, it's extremely good at writing kubernetes manifest. But also read on Kubenetes Ingress definitions, and see some of the many great youtube videos on that.

[Sampozzo]

@mysticaltech thank you very much, and sorry again. 😊

[gefloh]

@Sampozzo Please continue to ask also the potentially simple questions. I am also pretty new to this and would appreciate it.

[Sampozzo]

Thanks @gefloh, I'm reading two kubernetes books, a lot of documentation online, i did some tests on my local network but now I'm stuck in a similar production env like this on hetzner with load balancer.
I have a lot to learn and will do, any real example to expose an nginx over 80 and 443 is very appreciated, chatgpt did't helped 😅

[mysticaltech]

@Sampozzo Here's an example in the examples folder https://github.com/kube-hetzner/terraform-hcloud-kube-hetzner/tree/master/examples/tls

[Sampozzo]

@mysticaltech yes thanks!!!
Finally i have it working thanks to the sample.
NB: i tested it pointing a cloudflare proxyed domain, and it doesn't need to deploy a certificate in the cluster, it is issued by cloudflare.
Really great!

Here is the complete example if anyone in the future need it.

---
apiVersion: v1
kind: Namespace
metadata:
  name: test-namespace
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx
  namespace: test-namespace
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:latest
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: nginx-service
  namespace: test-namespace
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: nginx
---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-ingress
  namespace: test-namespace
  annotations:
    traefik.ingress.kubernetes.io/router.tls: "true"
    traefik.ingress.kubernetes.io/router.tls.certresolver: le
spec:
  tls:
    - hosts:
        - my.test.domain
  rules:
    - host: my.test.domain
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: nginx-service
                port:
                  number: 80

[maggie44]

@Sampozzo, did you change to NGINX from the default traefik to get this to work? Same configuration with the defaults and I only see 404 page not found from the load balancer, it is never reaching the services behind it. Yet when I deploy with type: LoadBalancer and let it create a new one, it all works fine.

Exceeded maxRedirects. Probably stuck in a redirect loop error when requesting the URL, testing with Cloudflare proxy enabled, but not working without the proxy either.

[Sampozzo]

@maggie44 no, i use the default traefik loadbalancer, the yaml i posted in my last message is working for me. Maybe you are accessing the LB by the IP, and it give you 404. You have to configure a dns name with the info in the ingress spec of the yaml to have it working (my.test.domain in the example)

[maggie44]

I took it all down and started up again with NGINX and all worked fine. Took it back down again and back up with Traefik, used the exact same yaml files and now it's not working again. Maybe something to do with the TLS certificates, does Traefik try and do something clever?

I guess there is a parallel question here on the advantages of Traefik over NGINX?

[Sampozzo]

I'm not an Expert, I'm learning kubernetes now, so i can't help sorry. I only can say that in my tests i used a domain proxied by cloudflare, so the certificate part is managed by cloudflare and not on kubernetes.

[maggie44]

Turns out the Cloudflare TLS setting was on Flexible in the Cloudflare control panel which causes the maxRedirects error. Changing it to Full seems to have resolved the issue.