For seasoned Kubernetes developers and administrators, kubectl is a command they run most of the time. The following steps will simplify your life, save you a ton of time, let you focus on more essential activities, and set you apart from the rest.
Using aliases
Most system administrators use aliases for an excellent reason—they save valuable time. Aliases in Linux are different names for commands, and they are mostly used to shorten the most frequently used commands; for example, ls -l becomes ll.
You can use the following aliases with kubectl to make your life easier.
k for kubectl
Yes—that’s right. By using the following alias, you can use k instead of typing kubectl:
| $ | alias k=’kubectl’ | ||||
| $ | k get node | ||||
| NAME | STATUS | ROLES | AGE | VERSION | |
| kind-control-plane | Ready | master | 5m7s | v1.26.1 | |
| kind-worker | Ready | <none> | 4m33s | v1.26.1 | |
That will save a lot of time and hassle.
Using kubectl –dry-run
kubectl –dry-run helps you to generate YAML manifests from imperative commands and saves you a lot of typing time. You can write an imperative command to generate a resource and append that with a –dry-run=client -o yaml string to generate a YAML manifest from the imperative command. The command does not create the resource within the cluster, but instead just outputs the manifest. The following command will generate a Pod manifest using –dry-run:
$ kubectl run nginx –image=nginx –dry-run=client -o yaml
apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: nginx
name: nginx
spec:
containers:
image: nginx
name: nginx
resources: {}
dnsPolicy: ClusterFirst
restartPolicy: Always
status: {}
And you now have the skeleton YAML file that you can edit according to your liking.
Now, imagine typing this command multiple times during the day! At some point, it becomes tiring. Why not shorten it by using the following alias?
$ alias kdr=’kubectl –dry-run=client -o yaml’
You can then use the alias to generate other manifests.
To generate a Deployment resource manifest, use the following command:
$ kdr create deployment nginx –image=nginx
You can use the dry run to generate almost all resources from imperative commands. However, some resources do not have an imperative command, such as a DaemonSet resource. You can generate a manifest for the closest resource and modify it for such resources. A DaemonSet manifest is very similar to a Deployment manifest, so you can generate a Deployment manifest and change it to match the DameonSet manifest.
Now, let’s look at some of the most frequently used kubectl commands and their possible aliases.
kubectl apply and delete aliases
If you use manifests, you will use the kubectl apply and kubectl delete commands most of the time within your cluster, so it makes sense to use the following aliases:
$ alias kap=’kubectl apply -f’
$ alias kad=’kubectl delete -f’
You can then use them to apply or delete resources using the following commands:
$ kap nginx-deployment.yaml
$ kad nginx-deployment.yaml
While troubleshooting containers, most of us use busybox. Let’s see how to optimize it.
