Here’s a comprehensive guide comparing the oc (OpenShift CLI) and kubectl (Kubernetes CLI) commands, focusing on their differences, similarities, and real-world usage. This is especially useful for OpenShift developers or admins coming from Kubernetes backgrounds.

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📘 Comprehensive Guide: oc vs kubectl CLI

Aspect	oc (OpenShift CLI)	kubectl (Kubernetes CLI)
Definition	CLI tool for managing OpenShift resources and clusters	CLI tool for managing Kubernetes resources and clusters
Default Cluster	Targets OpenShift (Red Hat Kubernetes platform)	Targets any CNCF-compliant Kubernetes cluster
Installation	Installed with OpenShift tools or CRC	Comes bundled with most Kubernetes distributions
Resource Access	Supports all Kubernetes APIs + OpenShift APIs (e.g., Build, Route, ImageStream)	Supports only Kubernetes-native APIs
Customization	Includes extended functionality and OpenShift-specific templates	No built-in support for OpenShift-only resources
Login	Uses oc login with OpenShift OAuth	Uses kubectl config or kubeconfig files
Compatibility	Fully supports kubectl commands as aliases	Cannot access OpenShift-only resources

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✅ Similarities Between oc and kubectl

Feature	Example Command (same for both)	Description
Get Pods	oc get pods / kubectl get pods	Lists pods in current namespace
Describe Resource	oc describe pod <name> / kubectl describe pod <name>	Detailed pod description
Apply YAML	oc apply -f app.yaml / kubectl apply -f app.yaml	Apply resource configuration
Delete Resources	oc delete pod <name> / kubectl delete pod <name>	Delete a resource
Logs	oc logs <pod> / kubectl logs <pod>	Stream logs from a container
Port-forward	oc port-forward svc/myapp 8080:80	Forward local port to a service
Exec	oc exec -it <pod> -- /bin/bash	Get shell access to a pod

✅ Fact: Every valid kubectl command is also valid in oc.

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🔴 Differences: oc Adds OpenShift-Specific Features

Command	Only in oc	Purpose
oc new-app	Yes	Rapid app deployment from source/image
oc new-project	Yes	Create a new OpenShift project (namespace)
oc adm	Yes	OpenShift admin utility commands
oc rollout	Extended	Manage OpenShift-specific rollouts
oc status	Yes	Visual overview of current project
oc whoami	Yes	Check current OpenShift user
oc get route	Yes	View OpenShift routes (external access)
oc import-image	Yes	Import images into OpenShift image streams
oc policy	Yes	RBAC management for OpenShift
oc start-build	Yes	Trigger OpenShift BuildConfig
oc logs -f bc/<buildConfig>	Yes	Stream logs from OpenShift build

⚠️ kubectl does not support OpenShift-specific resources like Route, BuildConfig, DeploymentConfig, ImageStream.

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🧪 Example: Deploying a Sample App

Using kubectl (Kubernetes way):

kubectl apply -f deployment.yaml
kubectl apply -f service.yaml
Code language: CSS (css)

Using oc (OpenShift way):

oc new-app nodejs~https://github.com/sclorg/nodejs-ex.git
oc expose svc/nodejs-ex
Code language: JavaScript (javascript)

OpenShift simplifies workflows with oc new-app and oc expose.

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👩‍💻 Example: Working with Projects/Namespaces

# Create and switch in OpenShift
oc new-project myapp

# Create namespace in Kubernetes
kubectl create namespace myapp
kubectl config set-context --current --namespace=myapp
Code language: PHP (php)

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⚙️ oc adm (Admin Commands Exclusive to OpenShift)

Command	Purpose
oc adm diagnostics	Run cluster diagnostics
oc adm top	View resource usage like kubectl top
oc adm policy add-role-to-user	Manage RBAC easily
oc adm groups	Manage OpenShift user groups
oc adm node-logs	View node logs in OpenShift
oc adm drain	Drain node (similar to kubectl drain)

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🧠 When to Use What?

Use Case	Recommended CLI
Basic Kubernetes operations	kubectl or oc
OpenShift templates, routes, and builds	oc only
Admin tasks on OpenShift (RBAC, node mgmt)	oc adm
Scripting across clusters (K8s generic)	kubectl
Using CRC or OpenShift Online	oc preferred

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📌 Summary Table

Command Type	kubectl Support	oc Support
Kubernetes Resources	✅ Yes	✅ Yes
OpenShift Resources	❌ No	✅ Yes
CLI Alias of Each Other	✅ oc supports all kubectl	✅ Yes
Admin Commands	❌ Limited	✅ Full (oc adm)
Developer Productivity	❌ No templating	✅ Powerful templates, routes, builds

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💡 Tip: You can always alias kubectl to oc if you’re using OpenShift full-time:

alias kubectl='oc'
Code language: JavaScript (javascript)

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