How to Force Docker Clean Build Without Cache

To force Docker to perform a clean build without using cache, you need to add the --no-cache flag to your build command. For your specific case, the command would be:

docker build --no-cache -t u12_core -f u12_core .

This flag tells Docker to ignore any cached layers and rebuild the entire image from scratch, ensuring that all steps are executed again regardless of whether they appear to be unchanged.

Contents

• Understanding Docker Cache
• Primary Methods for Clean Builds
• Using the --no-cache Flag
• Alternative Approaches
• Docker Compose Solution
• Best Practices

Understanding Docker Cache

Docker build caching is designed to speed up the build process by storing intermediate layers. When you run docker build, Docker checks each step against the cache. If a step hasn’t changed, Docker uses the cached version instead of rebuilding it. This is why you see “Using cache” messages in your build output.

However, as you’ve discovered, this caching behavior can sometimes lead to inconsistencies where the container doesn’t reflect the expected state despite showing cached layers in the build process.

Primary Methods for Clean Builds

Using the --no-cache Flag

The most straightforward solution is using the --no-cache flag. According to Cloudbees, “Using Docker’s –no-cache option forces the container build process to skip all cached layers.”

For your specific command:

docker build --no-cache -t u12_core -f u12_core .

This will:

• Force Docker to execute every build step
• Download fresh base images when needed
• Create entirely new image layers
• Ignore all existing cache entries

Note: Clean builds take longer because Docker can’t leverage any cached layers, but they ensure complete consistency between your Dockerfile and the resulting image.

Alternative Approaches

Using --pull with --no-cache

Sometimes you may want to force a fresh pull of the base image as well. In this case, combine both flags:

docker build --no-cache --pull -t u12_core -f u12_core .

As one Stack Overflow user noted, “The --pull option did the trick for me. Just --no-cache, build still broke. Put in --pull as well, build worked!”

Using Cache Busting Arguments

For more controlled cache invalidation, you can use build arguments with changing values. As Bomberbot demonstrates:

docker build -t u12_core -f u12_core --build-arg CACHEBUST=$(date +%s) .

This approach:

• Adds a timestamp as a build argument
• Invalidates cache for that layer and all subsequent layers
• Allows caching for unchanged base layers
• Provides more granular control over cache invalidation

Docker Compose Solution

If you’re using docker-compose, the solution is similar but with a slightly different syntax:

docker-compose build --no-cache

Or for a specific service:

docker-compose build --no-cache u12_core

Best Practices

1. Use --no-cache strategically: While tempting, avoid using --no-cache for every build as it significantly slows down the build process.

2. Isolate cache-busting steps: Place build arguments or commands that change frequently near the end of your Dockerfile to minimize the impact on build performance.

3. Consider layer optimization: Review your Dockerfile to ensure you’re following best practices for Docker layering. This can help reduce the need for frequent cache invalidation.

4. Regular cache cleanup: Periodically clean up unused Docker cache to save disk space:

   bash

   docker system prune -a
   

The --no-cache flag should resolve your immediate issue with the aerospike installation not appearing in containers, as it forces a complete rebuild of every layer from scratch.

Sources

1. How to Use Docker Build Without Cache for Clean Builds - Cloudbees
2. How to force Docker for a clean build of an image - Stack Overflow
3. Docker Cache – How to Do a Clean Image Rebuild and Clear Docker’s Cache - Medium
4. docker build --no-cache | Build docker without cache - GoLinuxCloud
5. How to Make Docker Rebuild an Image Without Its Cache - HowToGeek
6. Docker Cache – How to Do a Clean Image Rebuild and Clear Docker’s Cache - Bomberbot

Conclusion

To force Docker to perform a clean build without cache, simply add the --no-cache flag to your build command. This ensures that Docker rebuilds every layer from scratch, addressing the inconsistency you’re experiencing with aerospike installation. For your specific use case, run:

docker build --no-cache -t u12_core -f u12_core .

Remember that clean builds take longer but guarantee complete consistency between your Dockerfile and the resulting image. Consider using cache-busting techniques or optimizing your Dockerfile structure for better performance in development workflows.