exercise cmds

CKAD
Core Concepts (13%)
kubectl create namespace mynamespace
kubectl run nginx --image=nginx --restart=Never -n mynamespace
kubectl run nginx --image=nginx --restart=Never --dry-run -o yaml > myfile.yaml
kubectl run busybox --image=busybox --command --restart=Never -it -- env   #withoutput
kubectl run busybox --image=busybox --command --restart=Never -- env #with
kubectl logs busybox
kubectl run busybox --image=busybox --restart=Never -o yaml --dry-run --command env > myfile.yaml
kubectl apply -f myfile.yaml
kubectl create namespace myns --dry-run -o yaml 
kubectl config set-context $(kubectl config current-context) --namespace=prod
kubectl get pods --all-namespaces
kubectl get pods --namespace=research
kubectl get pods -n research
kubectl run nginx --image=nginx --restart=Never --port=80
kubectl set image pod/nginx nginx=nginx:1.7.1
kubectl describe pod nginx
kubectl get pod nginx -w
kubectl get pod nginx -o wide
kubectl get pod nginx -o yaml
kubectl create quota myrq --hard=cpu=1,memory=1g,pod=2 --dry-run -o yaml
kubectl run busybox --image=busybox -it --restart=Never -- /bin/sh -c "echo hello world"
kubectl run busybox --image=busybox -it --restart=Never -- echo "hello world"
kubectl run busybox --image=busybox -it --rm --restart=Never -- echo "hello world"
kubectl run nginx --image=nginx --restart=Never --env=val1=val2 
kubectl exec -it nginx -- env
kubectl run nginx --image=nginx --env=val1=val2 -it --rm -- env 


Pod design (20%)
Labels and annotations

Kubectl run nginx1 --image=nginx --labels=app=v1
Kubectl get pods --show-labels
kubectl edit pod <pod name>
Kubectl label pod nginx2 app=v2 –-overwrite
Kubectl get pod –l app
Kubectl get pods –l app=v2
Kubectl get pods –-selector=app=v2
Kubectl label pod nginx1 app-
kubectl label nodes node01 size=large
Kubectl explain pod.spec
Kubectl annotate pod nginx description=”my pod desc”
Kubectl describe pod nginx | grep –i “annotation”
Kubectl annotate pod nginx description-
Kubectl delete pod nginx{1..3}
kubectl delete pod nginx --force --grace-period=0
Deployments
kubectl run nginx --image=nginx:1.7.8 --replicas=2 --port=80
kubectl create deployment nginx --image=nginx:1.7.8 --dry-run -o yaml > myfile.yaml
kubectl get deploy nginx -o yaml
kubectl get pod ngninx-dsdsffssa -o yaml
kubectl get pod -l run=nginx
kubectl rollout status deploy nginx
kubectl set image deploy/nginx nginx=ngninx:1.7.9
kubectl edit deployment my-deployment
kubectl rollout history deploy nginx
kubectl rollout undo deploy nginx --to-revision=2
kubectl rollout history deploy nginx --revision=6
kubectl rollout pause deploy nginx
kubectl rollout resume deploy nginx
kubectl scale deploy nginx --replicas=5
kubectl autoscale deploy nginx --min=5 --max=10 --cpu-percent=80
kubectl delete deploy nginx
kubectl delete hpa nginx

port forwarding 
kubectl port-forward pods/redis-master-765d459796-258hz 7000:6379
kubectl port-forward deployment/redis-master 7000:6379
kubectl port-forward replicaset/redis-master 7000:6379
kubectl port-forward service/redis-master 7000:6379


congifmaps

kubectl create configmap config --from-literal=foo=lala --from-literal=foo2=lolo
kubectl get configmap config -o yaml
kubectl describe cm config
kubectl create cm config2 --from-file=config.txt
kubectl create cm config3 --from-env-file=config.env


requests and limits
kubectl run nginx --image=nginx --restart=Never --requests="cpu=100m,memory=256Mi" --limits="cpu=200m,memory=512Mi"

secrets
kubectl create secret generic secretname --from-literal=passoword=pass
kubectl edit secrets mysecret
kubectl create secret generic secretname --from-file=username
kubectl get secret secretname -o yaml
echo YWRtaW4K | base64 -d

serviceaccounts
kubectl get sa --all-namespaces
kubectl create serviceaccount myuser
kubectl get sa default -o yaml > s.yaml
kubectl run nginx --image=nginx --restart=Never --serviceaccount=myuser -o yaml --dry-run > pod.yaml

Observability (18%)
Liveness and readiness probes
kubectl explain pod.spec.containers.livenessProbe.exec
kubectl explain pod.spec.containers.livenessProbe
kubectl describe pod nginx | grep -i liveness
kubectl describe pod nginx | grep -i readiness

Logging
kubectl logs busybox
kubectl logs busybox -f
kubectl logs material-information-vue-5f566d89c-pz2rz flask -f

CPU/memory utilization for nodes
kubectl top node
kubectl top pod 

services
kubectl expose pod redis --port=6379 --name redis-service
kubectl run ngninx --image=nginx --restart=Never --port=80 --expose
kubectl get svc nginx
kubectl get ep or endpoints
kubectl edit svc nginx 
kubectl delete svc nginx
kubectl delete pod nginx

kubectl run foo --image=dgkanatsios/simpleapp --labels=app=foo --port=8080 --replicas=3
kubectl get pods -l app=foo -o wide
wget -o- podip:8080
kubectl expose deploy foo --port=6262 --target-port=8080
wget -o- SERVICE_CLUSTER_IP:6262 


State Persistence
kubectl exec -it busybox -c busybox -- /bin/sh
kubectl cp busybox:/etc/passwd ./passwd 


Taints & Tolerations
kubectl taint nodes node-name key=value:taint:NoSchedule
kubectl taint nodes node-name key=value:taint:NoExecute
kubectl taint nodes node-name key=value:taint:PreferNoSchedule
kubectl taint nodes master node-role.kubernetes.io/master:NoSchedule-

networkpolicy

kubectl get networkpolicy