Why does my Kubernetes Service only work sometimes on EKS?

After much investigation, we were fighting a number of issues: * Our application didn't always behave the way we were expecting. Always check that first. * In our Kubernetes Service manifest, we had set the externalTrafficPolicy: Local, which probably should work, but was causing us problems. (This was with using Classic Load Balancer) service.beta.kubernetes.io/aws-load-balancer-type: "clb". So if you have problems with CLB, either remove the externalTrafficPolicy or explicitly set it to the default "Cluster" value.

So our manifest is now:kind: ServiceapiVersion: v1metadata: name: apollo-service annotations: service.beta.kubernetes.io/aws-load-balancer-type: "clb" service.beta.kubernetes.io/aws-load-balancer-ssl-cert: "arn:aws:acm:REDACTED" service.beta.kubernetes.io/aws-load-balancer-ssl-ports: "443" service.beta.kubernetes.io/aws-load-balancer-backend-protocol: "http"
spec: externalTrafficPolicy: Cluster selector: app: apollo ports: - name: http protocol: TCP port: 80 targetPort: 80 - name: https protocol: TCP port: 443 targetPort: 80 type: LoadBalancer

adding

service.beta.kubernetes.io/aws-load-balancer-ssl-ports: "443"service.beta.kubernetes.io/aws-load-balancer-backend-protocol: "http"

Fixed this for me