Kubernetes Imperative vs Declarative

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# Create a POD and Run
kubectl run --image=nginx nginx

# Create a Deployment
kubectl create deployment --image nginx nginx

# Expose and Create a Deployment
kubectl expose deployment nginx --port=80

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# Edit Deployment
kubectl edit deployment nginx

# Scale Deployment
kubectl scale deployment nginx --replicas=5

# Update Image Deployment
kubectl set image deployment nginx nginx=nginx:1.18

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# Create with YAML
kubectl create -f nginx.yml

# Replace with YAML
kubectl replace --force -f nginx.yml

# Delete with YAML
kubectl delete -f nginx.yml

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# Apply a file
kubectl apply -f nginx.yml

# Apply files
kubectl apply -f /path/to/files

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# Create a NGINX POD
kubectl run nginx --image=nginx

# Generate POD Manifest YAML file (-o yaml). Don't create it(--dry-run)
kubectl run nginx --image=nginx  --dry-run=client -o yaml

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# Create a Deployment
kubectl create deployment --image=nginx nginx

# Generate Deployment YAML file (-o yaml). Don't create it(--dry-run)
kubectl create deployment --image=nginx nginx --dry-run=client -o yaml

# Generate Deployment with 4 Replicas
kubectl create deployment nginx --image=nginx --replicas=4

# You can also scale a deployment using the kubectl scale command.
kubectl scale deployment nginx --replicas=4

# Another way to do this is to save the YAML definition to a file.
kubectl create deployment nginx --image=nginx--dry-run=client -o yaml > nginx-deployment.yaml

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# Create a Service named redis-service of type ClusterIP to expose pod redis on port 6379
kubectl expose pod redis --port=6379 --name redis-service --dry-run=client -o yaml
# (This will automatically use the pod's labels as selectors)

# Or
kubectl create service clusterip redis --tcp=6379:6379 --dry-run=client -o yaml
# (This will not use the pods labels as selectors, instead it will assume selectors as app=redis. You cannot pass in selectors as an option. So it does not work very well if your pod has a different label set. So generate the file and modify the selectors before creating the service)

# Create a Service named nginx of type NodePort to expose pod nginx's port 80 on port 30080 on the nodes:
kubectl expose pod nginx --port=80 --name nginx-service --type=NodePort --dry-run=client -o yaml
# (This will automatically use the pod's labels as selectors, but you cannot specify the node port. You have to generate a definition file and then add the node port in manually before creating the service with the pod.)

# Or
kubectl create service nodeport nginx --tcp=80:80 --node-port=30080 --dry-run=client -o yaml
# (This will not use the pods labels as selectors)