kubectl

Nota:

• https://kubernetes.io/docs/reference/kubectl/cheatsheet/https://kubernetes.io/docs/reference/kubectl/ https://kubernetes.io/docs/reference/kubectl/

1. Useful
   1. kubectl create

      Nota:

      • Run kubectl create to see a list of objects that can be created with imperative commands.
   2. kubectl create deployment my-deployment --image=nginx

      Nota:

      • Create a deployment imperatively.
   3. kubectl create deployment my-deployment --image=nginx --dry-run -o yaml

      Nota:

      • Do a dry run to get some sample yaml without creating the object.
   4. kubectl create deployment my-deployment --image=nginx --dry-run -o yaml > deployment.yml

      Nota:

      • Save the yaml to a file.
   5. kubectl create -f deployment.yml

      Nota:

      • Create the object using the file.
   6. kubectl scale deployment my-deployment replicas=5 --record

      Nota:

      • Scale a deployment and record the command.
   7. kubectl describe deployment my-deployment
   8. kubectl apply -f FILENAME [flags]
   9. kubectl drain NODE [options]
   10. kubectl delete (-f FILENAME | TYPE [NAME | /NAME | -l label | --all]) [flags]
   11. kubectl describe (-f FILENAME | TYPE [NAME_PREFIX | /NAME | -l label]) [flags]
   12. kubectl exec POD [-c CONTAINER] [-i] [-t] [flags] [-- COMMAND [args...]]
   13. kubectl expose
   14. kubectl label
   15. kubectl logs POD [-c CONTAINER] [--follow] [flags]
   16. kubectl port-forward POD [LOCAL_PORT:]REMOTE_PORT [...[LOCAL_PORT_N:]REMOTE_PORT_N] [flags]
   17. kubectl uncordon NODE [options]
   18. kubectl version [--client] [flags]
   19. kubectl api-resources
   20. kubectl get pods <pod-name> --server-print=false
   21. kubecyl apply
       1. kubectl apply -f example-service.yaml

          Nota:

          • # Create a service using the definition in example-service.yaml.
       2. kubectl apply -f example-controller.yaml

          Nota:

          • # Create a replication controller using the definition in example-controller.yaml.
       3. kubectl apply -f <directory>

          Nota:

          • # Create the objects that are defined in any .yaml, .yml, or .json file within the &lt;directory&gt; directory.
   22. kubectl get
       1. kubectl get pods -o wide
       2. kubectl get replicationcontroller <rc-name>

          Nota:

          • # List the replication controller with the specified name in plain-text output format. Tip: You can shorten and replace the 'replicationcontroller' resource type with the alias 'rc'.
       3. kubectl get rc,services

          Nota:

          • # List all replication controllers and services together in plain-text output format.
       4. kubectl get ds

          Nota:

          • # List all daemon sets in plain-text output format.
       5. kubectl get pods --field-selector=spec.nodeName=server01

          Nota:

          • # List all pods running on node server01
       6. kubectl get pods -n kube-system
       7. kubectl get pods -n kube-system --selector k8s-app=calico-node
       8. kubectl get pv

          Nota:

          • kubectl get pv -o yaml&nbsp; _____to get the values and sort them&nbsp; --sort-by=.spec....
          1. kubectl get pv --sort-by=.spec.capacity.storage
   23. kubectl config get-contexts
   24. kubectl config current-context
   25. kubectl config use-context my-cluster-name
   26. kubectl config set-context --current --namespace=ggckad-s2
   27. kubectl config set-context gce --user=cluster-admin --namespace=foo \ && kubectl config use-context gce
   28. kubectl get pods -n beebox-mobile --kubeconfig /home/cloud_user/dev-k8s-config
   29. kubectl top po -n beebox-mobile --sort-by=cpu --selector=app=auth > /home/cloud_user/cpu-pod-name.txt
2. output systax
   1. kubectl [command] [TYPE] [NAME] -o <output_format>

      Nota:

      • The default output format for all&nbsp;kubectl&nbsp;commands is the human readable plain-text format. To output details to your terminal window in a specific format, you can add either the&nbsp;-o&nbsp;or&nbsp;--output&nbsp;flags to a supported&nbsp;kubectl&nbsp;command.
   2. Output format
      1. -o custom-columns=<spec>

         Nota:

         • Print a table using a comma separated list of&nbsp;custom columns.
         1. kubectl get pods <pod-name> -o custom-columns=NAME:.metadata.name,RSRC:.metadata.resourceVersion
      2. -o custom-columns-file=<filename>

         Nota:

         • Print a table using the&nbsp;custom columns&nbsp;template in the&nbsp;&lt;filename&gt;&nbsp;file.
         1. kubectl get pods <pod-name> -o custom-columns-file=template.txt

            Nota:

            • where the&nbsp;template.txt&nbsp;file contains: NAME RSRC metadata.name metadata.resourceVersion
      3. -o json

         Nota:

         • Output a JSON formatted API object.
      4. -o jsonpath=<template>

         Nota:

         • Print the fields defined in a&nbsp;jsonpath&nbsp;expression.
      5. -o jsonpath-file=<filename>
      6. -o name
      7. -o wide
      8. -o yaml
         1. kubectl get pod web-pod-13je7 -o yaml
3. kubectl get clusterrolebindings