Daniel, Accessing 30000 from sage should work. I suspect this is an issue with flannel and/or kube-proxy. Do you have kube-proxy running correctly on each machine? kube-proxy is necessary to set up the iptables rules that allow traffic forwarding for services.
Please see this doc for more info on debugging services in general. Particularly, the parts "Is the kube-proxy working?" section should be relevant. https://kubernetes.io/docs/tasks/debug-application-cluster/debug-service/#is-the-kube-proxy-working Ian On Mon, Sep 4, 2017 at 12:29 AM Daniel Suen <ttds...@gmail.com> wrote: > I have set up a k8s two-node cluster (with flannel cidr 10.244.0.0/16) on > Ubuntu for experimental purpose at home. The setup is pretty basic. > > I have docker is version 17.06-ce. I installed k8s and the two nodes are > reported as ready. > > ube@sage ~/k8s $ kubectl get nodes > NAME STATUS AGE VERSION > parsley Ready 3d v1.7.4 > sage Ready 3d v1.7.5 > > > I know the version has some discrepancies as I did a apt-get update on > sage. Then I deployed a simple helloworld webapp, which is a default > Mojolicious webapp listening on port 3000... > This is the service definition: > > apiVersion: v1 > kind: Service > metadata: > name: helloworld-service > labels: > app: helloworld > spec: > type: NodePort > ports: > - port: 3000 > nodePort: 30000 > protocol: TCP > selector: > app: helloworld > > And, > > kube@sage ~/k8s $ kubectl describe service > Name: helloworld-service > Namespace: default > Labels: app=helloworld > Annotations: <none> > Selector: app=helloworld > Type: NodePort > IP: 10.100.172.154 > Port: <unset> 3000/TCP > NodePort: <unset> 30000/TCP > Endpoints: 10.244.1.7:3000,10.244.1.8:3000,10.244.1.9:3000 > Session Affinity: None > Events: <none> > > Then, I fired up a deployment: > > kube@sage ~/k8s $ kubectl describe deployments > Name: helloworld-deployment > Namespace: default > CreationTimestamp: Sat, 02 Sep 2017 09:37:51 -0400 > Labels: app=helloworld > Annotations: deployment.kubernetes.io/revision=1 > Selector: app=helloworld > Replicas: 3 desired | 3 updated | 3 total | 3 available | 0 unavailable > StrategyType: RollingUpdate > MinReadySeconds: 0 > RollingUpdateStrategy: 25% max unavailable, 25% max surge > Pod Template: > Labels: app=helloworld > Containers: > helloworld: > Image: helloworld:1.0.0 > Port: 3000/TCP > Environment: <none> > Mounts: <none> > Volumes: <none> > Conditions: > Type Status Reason > ---- ------ ------ > Available True MinimumReplicasAvailable > Progressing True NewReplicaSetAvailable > OldReplicaSets: <none> > NewReplicaSet: helloworld-deployment-1481581006 (3/3 replicas created) > Events: <none> > > And sure, all the pods are run on parsley (sage is the k8s master, but > also plays the role as node): > > kube@sage ~/k8s $ kubectl get pods --output=wide > NAME READY STATUS RESTARTS > AGE IP NODE > helloworld-deployment-1481581006-6dgpp 1/1 Running 0 1d > 10.244.1.7 parsley > helloworld-deployment-1481581006-j47cj 1/1 Running 0 1d > 10.244.1.9 parsley > helloworld-deployment-1481581006-tmbxl 1/1 Running 0 1d > 10.244.1.8 parsley > > If I am on parsley, any of these work properly: > > curl http://parsley:30000/ > curl http://127.0.0.1:30000/ > > But, these do not work: > > curl http://sage:30000/ > curl http://[ip of sage]:30000/ > > On sage, all those curl commands listed above don't work...(it just times > out, i.e. after issuing the curl command, it kind of hangs there till it > times out) > > I don't know if I understand the documentation correctly. I know a service > is run through kube-proxies which are present on each node, and the port I > specified (30000) should be open for connection, which I checked with > netstat -tupln | grep "30000", and it is the case on both sage and parsley: > > kube@sage ~/k8s $ netstat -tupln | grep "30000" > (Not all processes could be identified, non-owned process info > will not be shown, you would have to be root to see it all.) > tcp6 0 0 :::30000 :::* LISTEN > - > > And, if I hit this port on either node should direct me to the pod (which > I don't quite understand how this can be done in this case, as all pods are > on one node, and no pods are running on sage). How can I troubleshooting > this? Or I misunderstand the documentation. > > I also do not quite understand what the IP of the service means: > 10.100.172.154 in the service description. > > Appreciate if someone can help me on this. Thanks! > > Daniel. > > > > > > -- > You received this message because you are subscribed to the Google Groups > "Kubernetes user discussion and Q&A" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to kubernetes-users+unsubscr...@googlegroups.com. > To post to this group, send email to kubernetes-users@googlegroups.com. > Visit this group at https://groups.google.com/group/kubernetes-users. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "Kubernetes user discussion and Q&A" group. To unsubscribe from this group and stop receiving emails from it, send an email to kubernetes-users+unsubscr...@googlegroups.com. To post to this group, send email to kubernetes-users@googlegroups.com. Visit this group at https://groups.google.com/group/kubernetes-users. For more options, visit https://groups.google.com/d/optout.
