Kubernetes kubectl commands cheatsheet

Collection of useful kubectl commands

Here is list of important kubectl commands cheatsheet of Kubernetes. 

Impersonate a user and group

kubectl get pods --as-group="somecompany:somecompany-teamname" --as="test"

Explain a resource

kubectl explain hpa
kubectl explain svc

Get nodes region and zone

kubectl get nodes
--label-columns failure-domain.beta.kubernetes.io/region,failure-domain.beta.kubernetes.io/zone

Get Arch, OS, Instance type and node type if kops

kubectl get nodes -o wide -L beta.kubernetes.io/arch -L beta.kubernetes.io/os -L beta.kubernetes.io/instance-type -L  kops.k8s.io/instancegroupkubectl get nodes -L beta.kubernetes.io/arch -L beta.kubernetes.io/os -L beta.kubernetes.io/instance-type -L  kops.k8s.io/instancegroup

Get node version and name only

kubectl get nodes -o custom-columns=NAME:.metadata.name,VER:.status.nodeInfo.kubeletVersion

Get scheduleable nodes

kubectl get nodes --output 'jsonpath={range $.items[*]}{.metadata.name} {.spec.taints[*].effect}{"\n"}{end}' | awk '!/NoSchedule/{print $1}'

Get all deployments nameonly

kubectl get deployment -o=jsonpath={.items[*].metadata.name}

Get one deployment only (first one)

kubectl get deployment -o=jsonpath={.items[0].metadata.name}

Get all pods statuses only

kubectl get pods -o=jsonpath=‘{.items[*].status.phase}’ --all-namespaces

Get pods qos

kubectl get pods --all-namespaces -o custom-columns=NAME:.metadata.name,NAMESPACE:.metadata.namespace,QOS-CLASS:.status.qosClass

Get images running

kubectl get pod -o=jsonpath='{.spec.containers[*].image}' --all-namespaces
    kubectl get pod -o=custom-columns=NAME:.metadata.name,IMAGE:.spec.containers[*].image --all-namespaces

Where is my pod running

kubectl get pods -n sock-shop -l name=carts -o wide

Check node/pod usage memory and cpu

kubectl top nodes
kubectl top pods

Check health of etcd

kubectl get --raw=/healthz/etcd

Check status of node autoscaler

kubectl describe configmap cluster-autoscaler-status -n kube-system

Get where pods are running from nodenames

kubectl get pod -o=custom-columns=NAME:.metadata.name,STATUS:.status.phase,NODE:.spec.nodeName --all-namespaceskubectl get pod -o=custom-columns=NODE:.spec.nodeName,NAME:.metadata.name --all-namespaces

Example sorting pods by nodeName:

kubectl get pods -o wide --sort-by="{.spec.nodeName}"

Example of getting pods on nodes using label filter:

for n in $(kubectl get nodes -l your_label_key=your_label_value --no-headers | cut -d " " -f1); do
        kubectl get pods --all-namespaces  --no-headers --field-selector spec.nodeName=${n}
  done

or by number of restarts

kubectl get pods --sort-by="{.status.containerStatuses[:1].restartCount}"

Example filtering by nodeName using — template flag:

$ kubectl get nodes  NAME                         STATUS                     AGE
  ip-254-0-90-30.ec2.internal   Ready                      2d
  ip-254-0-90-35.ec2.internal   Ready                      2d
  ip-254-0-90-50.ec2.internal   Ready,SchedulingDisabled   2d
  ip-254-0-91-60.ec2.internal   Ready                      2d
  ip-254-0-91-65.ec2.internal   Ready                      2d
  $ kubectl get pods --template '{{range .items}}{{if eq .spec.nodeName "ip-254-0-90-30.ec2.internal"}}{{.metadata.name}}{{"\n"}}{{end}}}{{end}}'  filebeat-000
  app-0000
  node-exporter-0000
  prometheus-000
 

Check pods which are not Runnning

kubectl get pods --field-selector=status.phase!=Running --all-namespaces

Sort Nodes by Role, Age and kubelet version

kubectl get nodes --sort-by={.metadata.labels."kubernetes\.io\/role"}
   kubectl get node --sort-by={.status.nodeInfo.kubeletVersion}
   watch kubectl get node --sort-by={.status.nodeInfo.kubeletVersion}
   watch "kubectl get nodes --sort-by={.metadata.labels.\"kubernetes\.io\/role\"}"
   kubectl get nodes --sort-by=".status.conditions[?(@.reason == 'KubeletReady' )].lastTransitionTime"

Query apiservers

kubectl get --raw=/apis
kubectl get --raw=/logs/kube-apiserver.log

Setup a deployment with limits and requests

·         kubectl run ken-test --image=docker/docker-curl -i --tty --limits='cpu=50m,memory=128Mi' --requests='cpu=50m,memory=128Mi'

·         kubectl delete deployment docker-test

Get events for an individual resource

kubectl get event --field-selector=involvedObject.name =foo -w

Get apiresources

 Check for an api resources available, this should show your crd api endpoints as well

·         kubectl api-resources

·         kubectl api-versions

  Check apiservices added (registered)

·         kubectl get apiservices.apiregistration.k8s.io

·         kubectl get apiservices.apiregistration.k8s.io v1beta1.metrics.k8s.io -o yaml

Check hpa (maybe because you have custom metrics enabled in prometheus)?

·         kubectl get hpa

·         kubectl get hpa --all-namespaces
   kubectl get --raw /apis/metrics.k8s.io

Kube Diff

·         kubectl alpha diff -h