README.md

Service Account

Service Account

Service Type

Tips and Tricks

For simulated Practice problems visit KillerCoda.

1. A nginx pod is deployed on node node01 with container port exposed at 80 and label app=myapp. Create a NodePort service named ng-svc to expose nginx pod on node Port 30002.

Setup

# copy these contents & create the pod
kubectl apply -f - <<EOF
apiVersion: v1
kind: Pod
metadata:
  creationTimestamp: null
  labels:
    run: nginx
  name: nginx
spec:
  nodeName: node01
  containers:
  - image: nginx
    name: nginx
    resources: {}
    ports:
      - containerPort: 80
  dnsPolicy: ClusterFirst
  restartPolicy: Always
status: {}
EOF

Solution

# create service yaml file
k create svc nodeport ng-svc --tcp=80:80 --target-port=80 --dry-run=client -o yaml > service.yaml

# update selector in service yaml file
apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: ng-svc
  name: ng-svc
spec:
  ports:
  - name: ports
    nodePort: 30002
    port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: myapp
  type: NodePort

# create service
k create -f service.yaml

# get the node ip address
k get nodes -o wide

# make request on the node ip with port 30002
wget -qO- <node01-ip>:30002

2. There exist 3 nginx pods with names pod-1, pod-2 & pod-3 with label app=frontend. If you make a request to each pod on their ip they will return responding from pod-x . Now create a service frontend with type ClusterIP exposing these pods as a service on port 80.

Try polling with this script to the service & see the results

# get the service ip
k get svc

# run
while true; do curl -s <service-ip>; sleep 1; done

# it will distribute request to the 3 created pods

Setup

# copy these contents & create the pod
kubectl apply -f - <<EOF
apiVersion: v1
kind: Pod
metadata:
  name: pod-1
  labels:
    app: frontend
spec:
  volumes:
  - name: html-volume
    emptyDir: {}
  initContainers:
  - name: init-c
    image: busybox
    volumeMounts:
    - name: html-volume
      mountPath: /usr/share/nginx/html
    command: ['sh', '-c', 'echo "responding from pod-1" > /usr/share/nginx/html/index.html']
  containers:
  - name: nginx
    image: nginx
    ports:
    - containerPort: 80
    volumeMounts:
    - name: html-volume
      mountPath: /usr/share/nginx/html
---
apiVersion: v1
kind: Pod
metadata:
  name: pod-2
  labels:
    app: frontend
spec:
  volumes:
  - name: html-volume
    emptyDir: {}
  initContainers:
  - name: init-c
    image: busybox
    volumeMounts:
    - name: html-volume
      mountPath: /usr/share/nginx/html
    command: ['sh', '-c', 'echo "responding from pod-2" > /usr/share/nginx/html/index.html']
  containers:
  - name: nginx
    image: nginx
    ports:
    - containerPort: 80
    volumeMounts:
    - name: html-volume
      mountPath: /usr/share/nginx/html
---
apiVersion: v1
kind: Pod
metadata:
  name: pod-3
  labels:
    app: frontend
spec:
  volumes:
  - name: html-volume
    emptyDir: {}
  initContainers:
  - name: init-c
    image: busybox
    volumeMounts:
    - name: html-volume
      mountPath: /usr/share/nginx/html
    command: ['sh', '-c', 'echo "responding from pod-3" > /usr/share/nginx/html/index.html']
  containers:
  - name: nginx
    image: nginx
    ports:
    - containerPort: 80
    volumeMounts:
    - name: html-volume
      mountPath: /usr/share/nginx/html
EOF

Solution

# create service yaml file
apiVersion: v1
kind: Service
metadata:
  name: frontend
spec:
  selector:
    app: frontend
  ports:
    - protocol: TCP
      port: 80
      targetPort: 80
  type: ClusterIP

# create service
k create -f service.yaml

3. There exist a bbox pod in setup namespace. Expose pod on port 80.

Setup

# copy these contents & create the pod
kubectl apply -f - <<EOF
apiVersion: v1
kind: Pod
metadata:
  creationTimestamp: null
  labels:
    run: busyboc
  name: bbox
spec:
  nodeName: node01
  containers:
  - image: busybox
    name: bbox
    resources: {}
    command: ["sh","-c","sleep 3600"]
    ports:
      - containerPort: 80
  dnsPolicy: ClusterFirst
  restartPolicy: Always
EOF

Solution

# create pod on port 80
 k expose pod bbox --port=80 --name=bbox-svc --namespace=setup

4. There exist a deployment named backend in setup namespace. Create a service dep-svc that expose the deployment on port 80.

Setup

# copy these contents & create the pod
kubectl apply -f - <<EOF
apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: backend
  name: backend
  namespace: setup
spec:
  replicas: 3
  selector:
    matchLabels:
      app: backend
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: backend
    spec:
      containers:
      - image: nginx
        name: nginx
        ports:
          - containerPort: 80
        resources: {}
EOF

Solution

# create deploy on port 80
 k expose deploy backend --name=dep-svc --type=ClusterIP --port=80 --namespace=setup