amila-ku/kubernetes-study

Material for Studying Kubernetes and Preparing for Kubernetes certificatios

kubernetes-study

Material for Studying Kubernetes and Preparing for Kubernetes certificatios

• Concepts Overview
• Get Started
• Certification Topics

Kubectl Examples

pods

Create Pods:

kubectl run --generator=run-pod/v1 fooweb --image=nginx
kubectl run --restart=Never fooweb --image=nginx

more about generator

Create Pods and Expose Port:

kubectl run --generator=run-pod/v1 fooweb --image=nginx --port=80
kubectl run --restart=Never fooweb --image=nginx --port=80

Create Pods, Expose Port and set Environment Variable:

kubectl run --generator=run-pod/v1 fooweb --image=nginx --port=80 --env="APPTYPE=foo"
kubectl run --restart=Never fooweb --image=nginx --port=80 --env="APPTYPE=foo"

Create Pods with requests, limits and service account:

kubectl run --generator=run-pod/v1 foobar --image=nginx — serviceaccount=foobar --requests=cpu=100m,memory=256Mi --limits=cpu=100m,memory=256Mi

Replication Controller

Creating Replication Controller:

kubectl run --generator=run/v1 fooweb --image=nginx

Deployment

Create Deployment:

kubectl run  fooweb --image=nginx
kubectl run --generator=apps/v1beta fooweb --image=nginx

use with --record to record changes

kubectl run fooweb --image=nginx --port=80 --record

Create Deployment, Expose Port and set Environment Variable:

kubectl run  fooweb --image=nginx --port=80 --env=APPTYPE=foo
kubectl run --generator=apps/v1beta fooweb --image=nginx --port=80 --env="APPTYPE=foo"
kubectl run hazelcast --image=hazelcast --env="DNS_DOMAIN=cluster" --env="POD_NAMESPACE=default"

Create Deployment and set Labels:

kubectl run fooweb --image=nginx --labels="app=hazelcast,env=prod" --port=80 --env="APPTYPE=foo"

Create Replicated Deployment

kubectl run nginx --image=nginx --replicas=5

Scale a Deployment

kubectl scale nginx --replicas=5

AutoScale a Deployment when [Horizontal Pod Autoscaling enabled] (https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale-walkthrough/)

kubectl autoscale deployment nginx-deployment --min=10 --max=15 --cpu-percent=80

Create Service for Deployment

kubectl expose deployment nginx --port=443 --target-port=8443 --name=nginx-https

Update, Rollback and Check Status

Update a Deployment

kubectl set image deployment/fooweb nginx=nginx:1.91

kubectl set resources deployment fooweb -c=nginx --limits=cpu=200m,memory=512Mi

Check Status of a Updated Deployment

kubectl rollout status deployment fooweb

Check Rollout History of a Deployment

kubectl rollout history deployment/fooweb

Check more details about a change

kubectl rollout history deployment/fooweb --revision=2

Rollback a change

kubectl rollout undo deployment/fooweb
kubectl rollout undo deployment/fooweb --to-revision=2

Start a Cron Job

Create Replicated Deployment

kubectl run pi --schedule="0/5 * * * ?" --image=perl --restart=OnFailure -- perl -Mbignum=bpi -wle 'print bpi(2000)'

Start a Job

Create Replicated Deployment

kubectl run pi --image=perl --restart=OnFailure -- perl -Mbignum=bpi -wle 'print bpi(2000)'

Expose Service, Pod

Create Service for Deployment

kubectl expose deployment nginx --port=443 --target-port=8443 --name=nginx-https

Create Service for Pod

kubectl expose pod fooweb --port=8080 --name=frontend

Create Service for ReplicationController with Protocol

kubectl expose rc streamer --port=4100 --protocol=udp --name=video-stream

Create Service for ReplicaSet

kubectl expose rs fooweb --port=80 --target-port=80 --name=fooweb-svc

kubectl referance