Kubernetes Cheatsheet

Kubernetes is a portable, extensible, open-source platform for managing containerized workloads and services, that facilitates both declarative configuration and automation. It has a large, rapidly growing ecosystem. Kubernetes services, support, and tools are widely available. Kubernetes provides you with a framework to run distributed systems resiliently. It takes care of scaling and failover for your application, provides deployment patterns, canary deployments, and more. In this blog post, I will mention Kubernetes commands which we need for most of the use-cases.

I will list down kubectl commands in the sections below as a quick reference to work with Kubernetes.

List Resources

  • Get list of all namespaces 
kubectl get namespaces
  • Get list of all pods 
kubectl get pods
  • Get list of all pods with detailed information like IP, Node Name etc... 
kubectl get pods -o wide
  • Get list of all pods running on a particular node server 
kubectl get pods --field-selector=spec.nodeName=[server-name]
  • Get list of all replication controllers and services 
kubectl get replicationcontroller,services
  • Get list of daemonsets 
kubectl get daemonset

Create Resources

  • Create a new namespace 
kubectl create namespace [namespace-name]
  • Create a new namespace from JSON or YAML file. 
kubectl create –f [filename]

Update Resources

To apply or update a resource use the kubectl apply command.

  • Create a new service with the definition contained in [service-config].yaml 
kubectl apply -f [service-config].yaml
  • Create a new replication controller with the definition contained in [controller-config].yaml 
kubectl apply -f [controller-config].yaml
  • Create the objects defined in any .yaml, .yml, or .json file in a directory 
kubectl apply -f [yaml-file/directory-name]
  • Edit a service config 
kubectl edit svc/[service-name]

Above command opens the file in your default editor. To choose another editor, specify it in front of the command:

KUBE_EDITOR=”[editor-name]” kubectl edit svc/[service-name]

Display the State of Resources

  • Get Details about Particular Node 
kubectl describe nodes [node-name]
  • Get Details about a Particular pod 
kubectl describe pods [pod-name]
  • Get Details about a Particular pod whose name and type are listed in pod.json 
kubectl describe –f pod.json
  • Get Details about a Particular pod managed by a specific replication controller 
kubectl describe pods [replication-controller-name]
  • Get Details about all pods 
kubectl describe pods

Delete Resources

  • Delete a pod using the name and type mentioned in pod.yaml 
kubectl delete -f pod.yaml
  • Delete all pods and services with a specific label 
kubectl delete pods,services -l [label-key]=[label-value]
  • Delete all pods 
kubectl delete pods --all

Execute Command

  • Get output from a command run on the first container in a pod 
kubectl exec [pod-name] -- [command]
  • Get output from a command run on a specific container in a pod 
kubectl exec [pod-name] -c [container-name] -- [command]
  • Run /bin/bash from a specific pod. The received output comes from the first container 
kubectl exec -ti [pod-name] -- /bin/bash

Print Container Logs

  • Print Logs from Pod 
kubectl logs [pod-name]
  • Stream Logs from Pod 
kubectl logs -f [pod-name]
  • Tail Logs from Pod (Print last 200 logs from pod) 
kubectl logs --tail=200 [pod-name]

Modify Kubeconfig Files

kubectl config command lets you view and modify kubeconfig files.

  • Get Current Context 
kubectl config current-context
  • Set cluster entry in kubeconfig 
kubectl config set-cluster [cluster-name] --server=[server-name]
  • Unset an entry in kubeconfig 
kubectl config unset [property-name]

Thank you for reading

Hope you find these resources useful. If you like what you read and want to see more about system design, microservices, and other technology-related stuff... You can follow me on

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