check all subcommands
kubectl config --help
view config
kubectl config view
kubectl check current context
kubectl config current-context
kubectl swtich context
kubectl use-context foo-context
in-line initialize a pod (not recommended)
kubectl run pod-name --image=foo
kubectl run pod-name --iamge=foo --port=8080
use the --dry-run=client flag to preview the object that would be sent to your cluster, without really submitting it
kubectl run pod-name --image=foo --dry-run=client
kubectl initialize objects from definition yaml file (recommended way)
kubectl apply -f pod-definition.yml
kubectl apply -f deployment-definition.yml
kubectl create config map thru from-literal
kubectl create configmap config-name --from-literal=key1=value1 \
--from-literal=key2=value2
kubectl create secret thru from-file
kubectl create configmap config-name --from-file=path-to-file
kubectl create secret thru from-literal
kubectl create secret generic secret-name --from-literal=key1=value1 \
--from-literal=key2=value2
kubectl create secret thru from-file
kubectl create secret generic secret-name --from-file=path-to-file
kubectl add taint to node
kubectl taint nodes node-name key=value:<taint-effect>
taint-effect including NoSchedule | PreferNoSchedule | NoExecute
kubectl list all objects
kubectl get all -n foo-ns
kubectl list pod
kubectl get pod -n foo-ns
kubectl list pod in all namespace
kubectl get pods --all-namespaces
kubectl list pod with selector
kubectl get pod --selector key=value
kubectl get pod --selector key1=value1,key2=value2
kubectl list service
kubectl get svc -n foo-ns
kubectl list element with regex
ubectl get deployment -n foo-ns --no-headers=true | awk '/pattern/{print $1}'
do deletion with regex
ubectl get deployment -n foo-ns --no-headers=true | awk '/pattern/{print $1}' | xargs kubectl delete -n foo-ns deployment
kubectl get elements with grep
kubectl get pod -n foo-ns | grep Evicted
do deletion with grep
kubectl get pod -n foo-ns | grep Evicted | awk '{print $1}' | xargs kubectl delete -n foo-ns pod
kubectl inline cmd
kubectl exec --namespace=foo-ns foo-pod -- sh -c 'cmd';
kubectl rollout status of a deployment
kubectl rollout status deployment foo-deployment
kubectl rollout history of a deployment
kubectl rollout history deployment foo-deployment
kubectl check the status of each revision individually by using the --revision flag
kubectl rollout history deployment nginx --revision=1
Use the --record flag to save the command used to create/update a deployment against the revision number. Then when we check the history of rollout, the change-cause is recorded
kubectl apply -f deployment.yml --record
kubectl rollout history deployment nginx --revision=1
kubectl roll back
kubectl rollout undo deployment foo-deployment
- install metrics-server
kubectl apply -f https://github.com/kubernetes-sigs/metrics-server/releases/latest/download/components.yaml
- kubectl get pod memory and cpu usage
kubectl top pod foo-pod -n foo-ns
cmds below can be used to verify if a service account have the premission to do operations in a specific namespaces
check if a service account can create deployment in a ns
kubectl auth can-i create deployment -n foo-ns --as system:serviceaccount:foo-ns:foo-sa
check if a service account can create service in a ns
kubectl auth can-i create service -n foo-ns --as system:serviceaccount:foo-ns:foo-sa
check if a service account can delete deployment in a ns
kubectl auth can-i delete deployment -n foo-ns --as system:serviceaccount:foo-ns:foo-sa
check if a service account can get deployments in a ns
kubectl auth can-i get deployment -n foo-ns --as system:serviceaccount:foo-ns:foo-sa