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Kubernetes: 6. Imperative Commands

  • Imperative commands are useful in quickly creating the resources on Kubernetes
kubectl
--dry-run -> When created with this option, Kubernetes just validates the definition and does not actually create the resource
-o=yaml -> Gets the output in YAML format

kubectl run nginx-pod --image=nginx:alpine 
-> Create a pod with name nginx-pod and image nginx:alpine

kubectl run httpd --image=httpd:alpine 
-> By default, run implies run-a-pod

kubectl run redis --image=redis:alpine --labels=tier=db 
-> Create a pod with name redis and image redis:alpine and labels set to tier=db

kubectl run custom-nginx --image=nginx --port=8080 
-> Create a pod with name custom-nginx and image nginx to run on port 8080

kubectl expose pod redis --port=6379 --name=redis-service 
-> Create a service with name redis-service to expose pod named redis on service-port 6379

kubectl create deployment webapp --image=kodekloud/webapp-color --replicas=3 
-> Create a deployment with name webapp and image set with 3 replicas

kubectl create ns dev-ns
-> Create a nanespace dev-ns

kubectl create deployment redis-deploy --namespace=dev-ns --image=redis --replicas=2 
-> Create a deployment

kubectl expose pod httpd --name=httpd --type=ClusterIP --port=80 --target-port=8080 
-> Expose a pod as service of type ClusterIP on the specifed ports  
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