Init containers in Kubernetes - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define an init container in a Pod spec.

Kubernetes

initContainers:
  - name: init-myservice
    image: busybox
    command: ["[1]", "-c", "echo Init container running"]

Drag options to blanks, or click blank then click option'

Abash

Bsh

Csleep

Drun

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'run' which is not a shell command

Using 'sleep' which delays but does not run commands

Using 'bash' which may not be available in busybox

The init container uses sh to run the shell command.

2fill in blank

medium

Complete the code to specify the init container image.

Kubernetes

initContainers:
  - name: init-db
    image: [1]

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Abusybox:1.35

Bnginx:latest

Cmysql:5.7

Dredis:alpine

Attempts:

3 left

💡 Hint

Common Mistakes

Using application images like nginx or mysql which are not typical for init containers

The init container uses the lightweight busybox:1.35 image for initialization tasks.

3fill in blank

hard

Fix the error in the init container command to run a shell script.

Kubernetes

initContainers:
  - name: setup
    image: busybox
    command: ["[1]", "-c", "echo Setup complete"]

Drag options to blanks, or click blank then click option'

Ash

Bbash

Ccmd

Dpowershell

Attempts:

3 left

💡 Hint

Common Mistakes

Using bash which may not be present

Using Windows shells like cmd or powershell which are invalid here

The sh shell is available in busybox and correctly runs the command.

4fill in blank

hard

Fill both blanks to define an init container that waits for a file before starting the main container.

Kubernetes

initContainers:
  - name: wait-for-file
    image: busybox
    command: ["[1]", "-c", "until test -f /tmp/ready; do [2] 1; done"]
containers:
  - name: main-app
    image: myapp
    volumeMounts:
      - name: shared-data
        mountPath: /tmp
volumes:
  - name: shared-data
    emptyDir: {}

Drag options to blanks, or click blank then click option'

Ash

Bbash

Csleep

Dcat

Attempts:

3 left

💡 Hint

Common Mistakes

Using bash which may not be in busybox

Using cat which does not pause

Using sleep as the command instead of inside the shell command

The init container uses sh to run the shell loop and sleep to wait between checks.

5fill in blank

hard

Fill all three blanks to create an init container that creates a directory and sets permissions before the main container starts.

Kubernetes

initContainers:
  - name: setup-dir
    image: busybox
    command: ["[1]", "-c", "mkdir -p /data [3] [2] 777 /data && echo Directory ready"]
    volumeMounts:
      - name: data-volume
        mountPath: /data
containers:
  - name: app
    image: myapp
    volumeMounts:
      - name: data-volume
        mountPath: /data
volumes:
  - name: data-volume
    emptyDir: {}

Drag options to blanks, or click blank then click option'

Ash

Bchmod

C&&

Dbash

Attempts:

3 left

💡 Hint

Common Mistakes

Using bash which may not be available

Using single & instead of && which causes syntax errors

Using wrong commands for permissions

The init container uses sh to run commands, chmod to set permissions, and && to chain commands.