Volume vs bind mount decision in Docker - Hands-On Comparison

Volume vs Bind Mount Decision in Docker

📖 Scenario: You are working on a Docker project where you need to decide how to store data generated by your containers. You want to understand the difference between Docker volumes and bind mounts to choose the best option for your use case.Imagine you have a simple web application container that needs to save logs and configuration files. You want to set up the data storage correctly to keep your data safe and easy to manage.

🎯 Goal: Learn how to create a Docker volume and a bind mount, understand their differences, and decide which one to use by running containers with each method.

📋 What You'll Learn

Create a Docker volume named app_data

Create a bind mount to a local directory /tmp/app_config

Run a container using the volume to store logs

Run a container using the bind mount to access configuration files

Print the contents of the stored files to verify data storage

💡 Why This Matters

🌍 Real World

Developers and system administrators often need to manage persistent data in Docker containers. Choosing between volumes and bind mounts affects data safety, portability, and ease of backup.

💼 Career

Understanding volumes and bind mounts is essential for Docker container management, a key skill in DevOps roles and cloud infrastructure management.

1

Create a Docker volume named app_data

Use the Docker CLI command docker volume create app_data to create a volume called app_data.

Docker

# Create a Docker volume named app_data
# Your code here

Need a hint?

Use the docker volume create command followed by the volume name.

2

Create a bind mount directory /tmp/app_config

Create a local directory /tmp/app_config on your host machine using the command mkdir -p /tmp/app_config.

Docker

docker volume create app_data
# Create a local directory /tmp/app_config
# Your code here

Need a hint?

Use the mkdir -p command to create the directory including parent directories if needed.

3

Run containers using the volume and bind mount

Run two Docker containers: one named log_container that uses the volume app_data mounted at /app/logs, and another named config_container that uses the bind mount /tmp/app_config mounted at /app/config. Use the busybox image and run the command sh -c "echo 'test' > /app/logs/log.txt" in log_container and sh -c "echo 'config' > /app/config/config.txt" in config_container.

Docker

docker volume create app_data
mkdir -p /tmp/app_config
# Run log_container with volume app_data mounted at /app/logs
# Run config_container with bind mount /tmp/app_config mounted at /app/config
# Your code here

Need a hint?

Use docker run --name [container_name] -v [volume_or_path]:[container_path] to mount volumes or bind mounts.

4

Display the contents of the stored files from both containers

Use docker cp <container_name>:<file_path> - to print the contents of /app/logs/log.txt from log_container and /app/config/config.txt from config_container. Use echo to label each output.

Docker

docker volume create app_data
mkdir -p /tmp/app_config
docker run --name log_container -v app_data:/app/logs busybox sh -c "echo 'test' > /app/logs/log.txt"
docker run --name config_container -v /tmp/app_config:/app/config busybox sh -c "echo 'config' > /app/config/config.txt"
# Print contents of /app/logs/log.txt from log_container
# Print contents of /app/config/config.txt from config_container
# Your code here

Need a hint?

Use docker cp [container_name]:[file_path] - to print file contents from stopped containers.