Common container startup failures in Docker - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the command to start a Docker container in detached mode.

Docker

docker run [1] nginx

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

A--name

B--rm

C-p

D-d

Attempts:

3 left

💡 Hint

Common Mistakes

Using '--rm' which removes the container after it stops.

Using '-p' which is for port mapping.

Using '--name' which names the container.

The '-d' flag runs the container in detached mode, allowing it to run in the background.

2fill in blank

medium

Complete the command to map port 8080 on the host to port 80 in the container.

Docker

docker run -p [1]:80 nginx

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

A8080

B443

C80

D3000

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the ports and using '80:8080' which maps the wrong way.

Using port 443 which is for HTTPS by default.

Using port 3000 which is unrelated here.

Port 8080 on the host is mapped to port 80 inside the container using '-p 8080:80'.

3fill in blank

hard

Fix the error in the Dockerfile to set the working directory.

Docker

WORKDIR [1]/app

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

Ausr/local

B/usr/local

C/usr/local/

Dusr/local/

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting the leading slash causing path errors.

Adding trailing slashes inconsistently.

Using relative paths instead of absolute.

The WORKDIR path must be absolute, starting with a slash '/' to avoid errors.

4fill in blank

hard

Fill both blanks to create a Docker volume mount for persistent data.

Docker

docker run -v [1]:[2] nginx

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

A/host/data

B/container/data

C/data

D/var/lib

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping host and container paths.

Using relative paths instead of absolute.

Using system directories that may cause permission issues.

The volume mount syntax is '-v host_path:container_path'. Here, '/host/data' is the host directory and '/container/data' is the container directory.

5fill in blank

hard

Fill all three blanks to write a Dockerfile command that copies files and sets environment variables.

Docker

COPY [1] [2]
ENV [3]=production

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

Asrc/

B/app/

CNODE_ENV

Ddist/

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong source or destination paths.

Forgetting to set environment variables correctly.

Mixing up COPY and ADD commands.

The COPY command copies 'src/' directory to '/app/' in the container. ENV sets the environment variable 'NODE_ENV' to 'production'.