Kubernets commands

k8s.txt

minikube version
minikube start
minikube start --vm-driver=virtualbox
minikube status
kubectl version
kubectl cluster-info
kubectl get componentstatuses
kubectl get events
kubectl get pods --all-namespaces
kubectl get services --all-namespaces

$ docker login quay.io

kubectl run flask --image=quay.io/kubernetes-for-developers/flask --port=5000 --save-config
deployment.apps "flask" created

kubectl get deployments
kubectl get deployment flask -o json

$ kubectl get replicaset

$ kubectl get pods
NAME                     READY     STATUS    RESTARTS   AGE
flask-6b79cdfc78-prjsx   1/1       Running   0          18s

$ kubectl port-forward flask-84f75f46d4-lsxp7 5000:5000
open 'http://localhost:5000/'
CTRL+C

kubectl proxy

kubectl logs flask-84f75f46d4-lsxp7

$ kubectl delete deployment flask
deployment.extensions "flask" deleted

$ kubectl get deployments
No resources found.

kubectl run nodejs --image=quay.io/kubernetes-for-developers/nodejs:0.2.0 --port=3000
kubectl run --help
kubectl run -i -t alpine-interactive --image=alpine -- sh
kubectl run -i -t python-interactive --image=quay.io/kubernetes-for-developers/flask:latest --command -- /bin/sh

kubectl run nodejs --image=quay.io/kubernetes-for-developers/nodejs:0.2.0 --port=3000

$ kubectl get pods
NAME                      READY     STATUS    RESTARTS   AGE
nodejs-5b985b9776-542c9   1/1       Running   0          3m
$ kubectl exec nodejs-5b985b9776-542c9 -it -- /bin/sh
/src # 

echo Aliasing tools
alias mk='/usr/local/bin/minikube'
alias k='kubectl'

k describe deployment nodejs

echo Filtering labels
k get pods -l run=nodejs

echo Shown columns labels
k get pods -L run
k get pods -L run,pod-template-hash

k run flask --image=quay.io/kubernetes-for-developers/flask:latest
k describe deployment flask
k describe replicaset flask
k describe pod flask

echo Create a service based on a resource that is already operating within the cluster
$ k expose deploy flask --port 5000
service "flask" exposed

$ k get services
NAME         TYPE        CLUSTER-IP      EXTERNAL-IP   PORT(S)    AGE
flask        ClusterIP   10.100.231.71   <none>        5000/TCP   52s
kubernetes   ClusterIP   10.96.0.1       <none>        443/TCP    7d

k describe service flask

$ k exec flask-7bdd449f7f-hxk64 -it -- /bin/sh
/ # env
KUBERNETES_PORT=tcp://10.96.0.1:443
KUBERNETES_SERVICE_PORT=443
HOSTNAME=flask-7bdd449f7f-hxk64
SHLVL=1
HOME=/root
TERM=xterm
KUBERNETES_PORT_443_TCP_ADDR=10.96.0.1
PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
KUBERNETES_PORT_443_TCP_PORT=443
KUBERNETES_PORT_443_TCP_PROTO=tcp
KUBERNETES_PORT_443_TCP=tcp://10.96.0.1:443
KUBERNETES_SERVICE_PORT_HTTPS=443
PWD=/
KUBERNETES_SERVICE_HOST=10.96.0.1

echo Creating NodePort service
k expose deploy flask --port 5000 --type=NodePort
k get service flask -o yaml

telnet $(minikube ip) 31855

$ minikube service flask --url
http://192.168.99.100:31855

echo Openning service on default browser
$ minikube service flask
Opening kubernetes service default/flask in default browser...

$ minikube service list
|-------------|----------------------|-----------------------------|
|  NAMESPACE  |         NAME         |             URL             |
|-------------|----------------------|-----------------------------|
| default     | flask                | http://192.168.99.100:31855 |
| default     | kubernetes           | No node port                |
| kube-system | default-http-backend | http://192.168.99.100:30001 |
| kube-system | kube-dns             | No node port                |
| kube-system | kubernetes-dashboard | http://192.168.99.100:30000 |
|-------------|----------------------|-----------------------------|

$ kubectl run redis --image=docker.io/redis:alpine
deployment.apps "redis" created

$ k get pods
NAME                     READY     STATUS    RESTARTS   AGE
flask-7bdd449f7f-spj5q   1/1       Running   0          19m
redis-84bc6bb5db-ws468   1/1       Running   0          36s

$ k exec -it redis-84bc6bb5db-ws468 -- /bin/sh
/data # ps aux
PID   USER     TIME   COMMAND
    1 redis      0:00 redis-server
   13 root       0:00 /bin/sh
   17 root       0:00 ps aux
/data # which redis-server
/usr/local/bin/redis-server
/data # redis-server --version
Redis server v=4.0.9 sha=00000000:0 malloc=jemalloc-4.0.3 bits=64 build=cce7cc41d26597f7
/data # exit

$ kubectl expose deploy redis --port=6379 --type=NodePort
service "redis" exposed

$ k get pods
NAME                     READY     STATUS    RESTARTS   AGE
flask-7bdd449f7f-spj5q   1/1       Running   0          28m
redis-84bc6bb5db-ws468   1/1       Running   0          9m

$ k exec flask-7bdd449f7f-spj5q -it -- sh
/ # nslookup redis.default
nslookup: can't resolve '(null)': Name does not resolve

Name:      redis.default
Address 1: 10.101.252.188 redis.default.svc.cluster.local
/ # 

kubectl get deploy flask -o yaml --export > flask_deployment.yaml

kubectl replace -f flask_deployment.yaml
deployment "flask" replaced

kubectl rollout status deployment/flask
kubectl rollout history deployment/flask

minikube delete