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Kubernetes commands you should definitely know!

Prerequisite to Practice Along

1. Kubernetes Cluster
2. kubectl CLI tool Installation Link: Kubernetes Tools Play with Kubernetes Get started with Minikube minikube start

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Explanation: This command sets up Minikube, a tool for running Kubernetes clusters locally for development purposes.

Check Kubectl

kubectl version --client
Explanation: This command checks the version of the installed Kubectl client.

Set Context for Cluster in different cloud providers
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# Connect to EKS
aws eks --region <region> update-kubeconfig --name <cluster-name>

# Connect to AKS
az aks get-credentials --resource-group <resource-group> --name <cluster-name>

# Connect to GKE
gcloud container clusters get-credentials <cluster-name> --region <region>
Explanation: These commands set the context for the specified cloud-managed Kubernetes clusters, allowing subsequent commands to interact with the chosen cluster.

kubeconfig file
The kubeconfig file is a crucial part of managing Kubernetes configurations, stored at ~/.kube/config by default. To check the current active context (cluster and user), use:

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kubectl config current-context
Explanation: This command displays the name of the current Kubernetes context, which represents the cluster that kubectl commands will interact with.

Manifest File - Creation, Deletion, and Editing Commands
A Kubernetes manifest file is a short YAML or JSON document that defines how a specific cluster resource should be configured and managed. It declares the desired state, allowing Kubernetes to maintain that state in the cluster.

Kubernetes Deployment:
Deployment Documentation
Deployment is a blueprint for running and managing application instances, ensuring the specified number of pods are running. It also manages aspects like the container image, configurations, and enables seamless updates, scalability, and self-healing.

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# Create a Deployment using Manifest file
kubectl apply -f deployment.yaml

# Delete an object using Manifest file
kubectl delete -f deployment.yaml

# Edit a Deployment using Manifest file
kubectl apply -f deployment.yaml
Explanation: These commands demonstrate how to create, delete, and edit Kubernetes resources using YAML manifest files.

GET Commands (Status)
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# Get commands to check the status
kubectl get pods
kubectl get services
kubectl get deployments
Explanation: These commands retrieve information about different Kubernetes resources, such as pods, services, and deployments.

Different Options with GET Commands
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# Get information in YAML format
kubectl get pods -o yaml

# Get information in JSON format
kubectl get services -o json
Explanation: These commands show how to retrieve information in different formats for more detailed view with better readability or automation.

Kubectl Describe
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# Describe a resource
kubectl describe pod <pod-name>
Explanation: This command provides detailed information about a specific Kubernetes resource, aiding in troubleshooting and understanding its configuration.

Imperative Commands
Explanation: Imperative commands allow quick actions without the need for manifest files.
Imperative Command Documentation

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# Create a Deployment imperatively
kubectl create deployment redis-deploy --image=redis --replicas=
Kubectl Create Commands
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# Create a Deployment with Redis image and 2 replicas
kubectl create deployment redis-deploy --image=redis --replicas=

# Create an Nginx Deployment
kubectl create deployment nginx-deploy --image=nginx
Explanation: These commands demonstrate creating deployments with specific images and replica counts.

Create a Pod
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# Create a Pod
kubectl run <pod-name> --image=<image-name>
Explanation: The kubectl run command creates a pod imperatively, allowing quick pod deployment without the need for a manifest file.

Edit Commands
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# Edit a Deployment imperatively
kubectl edit deployment <deployment-name>

# Scale a Deployment imperatively
kubectl scale deployment <deployment-name> --replicas=3
Explanation: Edit commands are used to modify existing deployments, either imperatively or by scaling the number of replicas.

⚠️ Certain fields of a resource, like its name or type, cannot be edited using kubectl edit as they are immutable. For such cases, the kubectl replace --force command is used to enforce an update by deleting and recreating the resource with the new configuration.

Kubectl Replace - Force
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# Replace and force update an object
kubectl replace --force -f <manifest_file>
Explanation: This command forcefully updates an object by replacing it with a new configuration.

Debugging Commands
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# Create a Deployment for debugging
kubectl create deployment debug-deploy --image=alpine

# View logs of a pod
kubectl logs <pod-name>

# Execute a command inside a container
kubectl exec -it <pod-name> -- /bin/sh
Explanation: These commands demonstrate debugging techniques, including viewing pod logs and executing commands inside a container.

Logging and Monitoring Commands
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# View logs of a pod
kubectl logs <pod-name>

# Display Resource Usage (CPU and Memory) of Pods
kubectl top pods
Explanation: These commands showcase how to view logs of a pod and display resource usage information for pods.

Kubectl Cheat Sheet
Official kubectl Cheat Sheet

Kubectl Reference Docs
Basic kubectl commands for getting a workload running on your cluster

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This markdown file organizes the provided commands and explanations into a structured and readable format.