Kubernetes Common Commands

Kubectl Get

1. Query node, nodes or node or no

$ kubectl get noNAME      STATUS    ROLES     AGE       VERSIONmaster1   Ready       master     16h         v1.9.2master2   Ready       master     16h         v1.9.2master3   Ready       master     16h         v1.9.2

2. Querying component Status, Componentstatuses or CS

$ kubectl get csNAME                 STATUS    MESSAGE             ERRORscheduler            Healthy   ok                  controller-manager   Healthy   ok                  etcd-1               Healthy   {"health":"true"}   etcd-2               Healthy   {"health":"true"}   etcd-0               Healthy   {"health":"true"}

3. Querying the name space, namespaces or NS

$ kubectl get nsNAME          STATUS    AGEdefault       Active    16hkube-public   Active    16hkube-system   Active    16h

All of the following queries, the default Defalut name space,-n Specify the name of the namespace, specify all the name of the space--all-namespaces
4. Query pod,pods or pod or PO

$ kubectl get podNAME                              READY     STATUS    RESTARTS   AGEkube-apiserver-master1            1/1       Running   0          16hkube-apiserver-master2            1/1       Running   0          16hkube-apiserver-master3            1/1       Running   0          16h

Add parameter-o wide to display the running node

$ kubectl get pod -n kube-system -o wideNAME                              READY     STATUS    RESTARTS   AGE       IP              NODEkube-apiserver-master1            1/1       Running   0          16h       192.168.6.101   master1kube-apiserver-master2            1/1       Running   0          16h       192.168.6.102   master2kube-apiserver-master3            1/1       Running   0          16h       192.168.6.103   master3

5. Query service,services or service or Svc

$ kubectl  get service --all-namespacesNAMESPACE     NAME         TYPE        CLUSTER-IP   EXTERNAL-IP   PORT(S)               AGEdefault             kubernetes   ClusterIP   10.96.0.1         <none>              443/TCP              16hkube-system   kube-dns      ClusterIP   10.96.0.10       <none>              53/UDP,53/TCP   16h

6.kind classification query, replicationcontrollers or RC, deployments or deploy, Daemonsets or DS

$ kubectl  get deployments --all-namespaces NAMESPACE     NAME       DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGEkube-system      kube-dns   1               1                  1                      1                    16h

7. Query All

$ kubectl  get all --all-namespaces

Kubectl Delete

1. Delete a node

$ kubectl delete node node1

2. Delete Pod

$ kubectl delete pod $(pod_name) -n $(namespace-name)

3. Delete Services

$ kubectl delete svc $(svc_name) -n $(namespace-name)

Update Maintenance

1. Manual dynamic extension Copy, scale

$ kubectl get Deployment -n test-appNAME          DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGEhello-world   3               3                  3                       3                   13h$ kubectl scale deployments hello-world --replicas=2 -n test-appdeployment "hello-world" scaled$ kubectl get Deployment -n test-app                            NAME          DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGEhello-world   2                2                  2                      2                   14h

2. According to the pod load automatic extension copy, Autoscale

$ kubectl autoscale deployments hello-world --min=2 --max=5 -n test-app

3. Update Rollback Pod,rolling-update
Rolling-update need to make sure the new version has different name,version and labels, otherwise it will error

$ kubectl rolling-update hello-world -f hello-world.yaml$ kubectl rolling-update hello-world --rollback

Problem Locator

1. Querying Object Details

$ kubectl describe pod kube-proxy-ftkx5 -n kube-system

2. Query log

$ kubectl logs -f  kube-proxy-ftkx5 -n kube-system

3. Enter container Run command, if Pod has more than one container, use-C to specify container

$ kubectl exec kube-dns-6f4fd4bdf-b7txf  -c dnsmasq hostname -n kube-systemkube-dns-6f4fd4bdf-b7txf

Kubernetes Common Commands