Multi container pod - Mock exam question

Kubernetes
#1

The question is:
kubectl config use-context cluster1

In the ckad-multi-containers namespace, create a pod named tres-containers-pod, which has 3 containers matching the below requirements:
• The first container named primero runs busybox:1.28 image and has OR-DER=FIRST environment variable.
• The second container named segundo runs nginx:1.17 image and is exposed at port 8080.
• The last container named tercero runs busybox:1.31.1 image and has OR-DER=THIRD environment variable.

NOTE: All pod containers should be in the running state.
• Is the primero container running?
• Is the primero container use busybox:1.28 image?
• Is the primero container environment variable well configured?
• Does the segundo container running?
• Does the segundo container use nginx:1.17 image?
• Is the segundo container expose at port 8080?
• Is the tercero container running?
• Is the tercero container use busybox:1.31.1 image?
• Is the tercero container environment variable well configured?

And the recommended solution is:

apiVersion: v1
kind: Pod
metadata:
creationTimestamp: null
labels:
run: primero
name: tres-containers-pod
namespace: ckad-multi-containers
spec:
containers:

  • env:
    • name: ORDER
      value: FIRST
      image: busybox:1.28
      name: primero
      command:
    • /bin/sh
    • -c
    • sleep 3600;
      resources: {}
  • image: nginx:1.17
    name: segundo
    ports:
    • containerPort: 8080
      resources: {}
  • env:
    • name: ORDER
      value: THIRD
      image: busybox:1.31.1
      name: tercero
      command:
    • /bin/sh
    • -c
    • sleep 3600;
      resources: {}
      dnsPolicy: ClusterFirst
      restartPolicy: Always
      status: {}

I would like to know why the following solution not adequate is and why I got a CrashLoopBackOff error.

apiVersion: v1
kind: Pod
metadata:
name: tres-containers-pod
namespace: ckad-multi-containers
spec:
containers:

  • name: primero
    image: busybox:1.28
    env:
    • name: ORDER
      value: “FIRST”
  • name: segundo
    image: nginx:1.17
    ports:
    • containerPort: 8080
  • name: tercero
    image: busybox:1.31.1
    env:
    • name: ORDER
      value: “THIRD”
#2

Can you please post these YAMLs in

code blocks

You have lost all the formatting and indentation which is part of the syntax of YAML, meaning we cannot check it.

#4 
apiVersion: v1
kind: Pod
metadata:
  name: tres-containers-pod
  namespace: ckad-multi-containers
spec:
  containers:
  - name: primero
    image: busybox:1.28
    env:
    - name: ORDER
      value: "FIRST"
  - name: segundo
    image: nginx:1.17
    ports:
    - containerPort: 8080
  - name: tercero
    image: busybox:1.31.1
    env:
    - name: ORDER
      value: "THIRD"
#5

You’re missing the command blocks for primero and tercero. These are needed, since busybox will immediately exit if it has nothing to do.

#6

why don´t we need a respective command (like
command:
- /bin/sh
- -c
- sleep 3600;
)
for segundo?

#7

segundo is running nginx which is a server, therefore the pod is doing something and does not exit.