• k8s
• StudyNotes
• k8sIngressService

k8s/StudyNotes/k8s Ingress Service

• Service [ clusterPort, nodePort]

  • Problem service nodePort > 30k, so need proxy server for port 80, 443 to this port.

• On cloud set to LoadBalancer, still nodePort + talks to cloud paltform to configure the LB

  • e.g. svc1 p38080, svc2 p38282, need yet another load-balancer
• Ingress - l7 loadbalancer config, path based.
  • Ingress controller Nginx, HAPROXY, traefik, GCE(Google), Istio
    • Not deployed by default

      • e.g. Deploy nginx-ingress-controller as Deployment + ConfigMap + Service + ServiceAccount

  • Ingress Resource

    apiVersion: networking.k8s.io/v1
    kind: Ingress
    spec: 
      rules:
      - host: wear.my-online-store.com 
        http:
          paths:
          - path: /wear
            pathType: Prefix
            backend:
              serviceName: wear-service
              servicePort: 80
          - path: /watch
            pathType: Prefix
            backend:
              serviceName: watch-service
              servicePort: 80

• From 1.20,  kubectl create ingress <ingress-name> --rule="host.com/path*=wear-svc:80" 

• Different ingress controllers can have annotations to set feature.

  • e.g. for nginx to strip /path/ when sending to backend service

      annotations:
        nginx.ingress.kubernetes.io/rewrite-target: /

  • or

    annotations:
      nginx.ingress.kubernetes.io/rewrite-target: /$2
    ...
    spec:
      rules:
      - http:
         paths:
         - path: /something(/|$)(.*)