Ambassador container pattern in Docker - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the Docker command to run an ambassador container named 'amb' that forwards traffic to port 8080.

Docker

docker run -d --name amb -p 9090:[1] ambassador-image

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

A8080

B3000

C443

D80

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong port number for forwarding.

Confusing host and container ports.

The ambassador container forwards traffic from port 9090 on the host to port 8080 inside the container.

2fill in blank

medium

Complete the Docker Compose service definition to link the ambassador container to the main app container.

Docker

services:
  app:
    image: myapp
  ambassador:
    image: ambassador-image
    depends_on:
      - [1]

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

Aproxy

Bdatabase

Ccache

Dapp

Attempts:

3 left

💡 Hint

Common Mistakes

Linking to unrelated services like database or cache.

Missing the depends_on field.

The ambassador container depends on the main app container to forward traffic correctly.

3fill in blank

hard

Fix the error in the ambassador container's environment variable to set the target host correctly.

Docker

environment:
  TARGET_HOST=[1]

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

A"app"

Bapp

C"localhost"

Dlocalhost

Attempts:

3 left

💡 Hint

Common Mistakes

Not quoting string values.

Using localhost instead of the service name.

Environment variables with string values must be quoted in Docker Compose YAML.

4fill in blank

hard

Fill both blanks to complete the ambassador container's command to forward traffic to the app service on port 8080.

Docker

command: ["[1]", "[2]"]

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

Aproxy

Bapp

C8080

Dstart

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'start' instead of 'proxy'.

Wrong port number.

The ambassador runs the 'proxy' command forwarding to port 8080.

5fill in blank

hard

Fill all three blanks to define a Docker Compose network and attach both app and ambassador containers to it.

Docker

networks:
  [1]:
    driver: [2]

services:
  app:
    image: myapp
    networks:
      - [3]
  ambassador:
    image: ambassador-image
    networks:
      - [3]

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

Afrontend_net

Bbridge

Dhost

Attempts:

3 left

💡 Hint

Common Mistakes

Using different network names in definition and services.

Using 'host' driver which is less common.

The network is named 'frontend_net' using the 'bridge' driver, and both services join it.