Master kubectl: Essential Commands and Tips for Kubernetes Management

We already know common Kubernetes terminology and concepts; to develop or simply run a small instance, you need to be familiar with typical operations. Learning kubectl is a fast way to get started.

1. kubectl Syntax

kubectl follows the pattern: kubectl [command] [TYPE] [NAME] [flags] command : sub‑command that operates on cluster resources, e.g., create, delete, describe, get, apply, etc.

TYPE : the resource type (case‑sensitive), which can be expressed in singular, plural, or short form. For example, pod, pods, and po are equivalent.

NAME : the name of the specific resource. If omitted, the command acts on all objects of the given TYPE.

flags : optional parameters for the sub‑command, such as -s to specify the API server URL.

Examples of specifying resources:

kubectl get pod pod1

kubectl get pods pod1 pod2

kubectl get pod/pod1 rc/rc1

kubectl get -f pod1.yaml -f pod2.yaml

kubectl create -f pod1.yaml -f rc1.yaml -f service1.yaml

2. kubectl Subcommands

kubectl offers a rich set of subcommands covering most operations on a Kubernetes cluster, including creation, deletion, inspection, configuration, and execution. The table below summarizes the most common subcommands.

3. Common Global Parameters

The following image lists the public startup parameters for kubectl.

4. Output Formats

kubectl can display results in various formats, selected with the -o flag.

5. Practical kubectl Examples

Below are common usage scenarios with the corresponding commands. kubectl create -f my-service.yaml -f my-rc.yaml Create resources from a directory containing YAML/JSON files: kubectl create -f <directory> List all pods: kubectl get pods List replication controllers and services: kubectl get rc,service Show detailed node information: kubectl describe nodes <node-name> Show detailed pod information: kubectl describe pods/<pod-name> Delete a pod defined in a YAML file: kubectl delete -f pod.yaml Delete all pods and services with a specific label:

kubectl delete pods,services -l name=<label-name>

Delete all pods: kubectl delete pods --all Execute a command inside a pod (default first container): kubectl exec <pod-name> date Execute a command in a specific container of a pod:

kubectl exec <pod-name> -c <container-name> date

Open an interactive bash shell in a container:

kubectl exec -it <pod-name> -c <container-name> /bin/bash

View container logs: kubectl logs <pod-name> Follow container logs (similar to tail -f):

kubectl logs -f <pod-name> -c <container-name>