Practice Test - Deploy Network Solution

ㅁ In this practice test we will install weave-net POD networking solution to the cluster. Let us first inspect the setup.

We have deployed an application called app in the default namespace. what is the state of the pd?

 

[NOT RUNNING]

$ kubectl get pod

NAME   READY   STATUS              RESTARTS   AGE
app    0/1     ContainerCreating   0          2m15s

 

ㅁ Inpect why the POD is not running

 

[Wrong image]

[Faulty start command]

[Node failed]

[No Network Configured]

 

$ kubectl describe pod app

$ kubectl describe pod app

Events:
  Type     Reason                  Age                 From               Message
  ----     ------                  ----                ----               -------
  Normal   Scheduled               4m5s                default-scheduler  Successfully assigned default/app to node01
  Warning  FailedCreatePodSandBox  4m3s                kubelet, node01    Failed to create pod sandbox: rpc error: code = Unknown desc = [failed to set up sandbox container "693a6f7ef3f8e1c40bcbd6f236b0abc154090ae389862989ddb5abee956624a8" network for pod "app": networkPlugin cni failed to set up pod "app_default" network: unable to allocate IP address: Post "http://127.0.0.1:6784/ip/693a6f7ef3f8e1c40bcbd6f236b0abc154090ae389862989ddb5abee956624a8": dial tcp 127.0.0.1:6784: connect: connection refused, failed to clean up sandbox container "693a6f7ef3f8e1c40bcbd6f236b0abc154090ae389862989ddb5abee956624a8" network for pod "app": networkPlugin cni failed to teardown pod "app_default" network: Delete "http://127.0.0.1:6784/ip/693a6f7ef3f8e1c40bcbd6f236b0abc154090ae389862989ddb5abee956624a8": dial tcp 127.0.0.1:6784: connect: connection refused]
  Normal   SandboxChanged          7s (x19 over 4m3s)  kubelet, node01    Pod sandbox changed, it will be killed and re-created.

 

ㅁ Deploy weave-net networking solution to the cluster

 

아래 weave-net 설치 경로를 찾기 위해서는 installing addon을 검색하여 weave-net을 찾는다.

kubectl apply -f "https://cloud.weave.works/k8s/net?k8s-version=$(kubectl version | base64 | tr -d '\n')"

serviceaccount/weave-net created
clusterrole.rbac.authorization.k8s.io/weave-net created
clusterrolebinding.rbac.authorization.k8s.io/weave-net created
role.rbac.authorization.k8s.io/weave-net created
rolebinding.rbac.authorization.k8s.io/weave-net created
daemonset.apps/weave-net created

 

$ kubectl get pods --all-namespaces 

NAMESPACE     NAME                                   READY   STATUS    RESTARTS   AGE
default       app                                    1/1     Running   0          7m16s
kube-system   coredns-f9fd979d6-d5fv4                1/1     Running   0          9m27s
kube-system   coredns-f9fd979d6-hrz9w                1/1     Running   2          9m42s
kube-system   etcd-controlplane                      1/1     Running   0          61m
kube-system   kube-apiserver-controlplane            1/1     Running   0          61m
kube-system   kube-controller-manager-controlplane   1/1     Running   0          61m
kube-system   kube-proxy-dflgk                       1/1     Running   0          61m
kube-system   kube-proxy-zk6gm                       1/1     Running   1          61m
kube-system   kube-scheduler-controlplane            1/1     Running   0          61m
kube-system   weave-net-22vm6                        2/2     Running   0          35s
kube-system   weave-net-vdjrs                        2/2     Running   0          35s