Building with Docker Build Cloud

To build using Docker Build Cloud, invoke a build command and specify the name of the builder using the --builder flag.

$ docker buildx build --builder cloud-<ORG>-<BUILDER_NAME> --tag <IMAGE> .

Use by default

If you want to use Docker Build Cloud without having to specify the --builder flag each time, you can set it as the default builder.

$ docker buildx use cloud-<ORG>-<BUILDER_NAME> --global

Changing your default builder with docker buildx use only changes the default builder for the docker buildx build command. The docker build command still uses the default builder, unless you specify the --builder flag explicitly.

If you use build scripts, such as make, we recommend that you update your build commands from docker build to docker buildx build, to avoid any confusion with regards to builder selection. Alternatively, you can run docker buildx install to make the default docker build command behave like docker buildx build, without discrepancies.

Use with Docker Compose

To build with Docker Build Cloud using docker compose build, first set the cloud builder as your selected builder, then run your build.

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Make sure you're using a supported version of Docker Compose, see Prerequisites.

$ docker buildx use cloud-<ORG>-<BUILDER_NAME>
$ docker compose build

In addition to docker buildx use, you can also use the docker compose build --builder flag or the BUILDX_BUILDER environment variable to select the cloud builder.

Loading build results

Building with --tag loads the build result to the local image store automatically when the build finishes. To build without a tag and load the result, you must pass the --load flag.

Loading the build result for multi-platform images is not supported. Use the docker buildx build --push flag when building multi-platform images to push the output to a registry.

$ docker buildx build --builder cloud-<ORG>-<BUILDER_NAME> \
  --platform linux/amd64,linux/arm64 \
  --tag <IMAGE> \
  --push .

If you want to build with a tag, but you don't want to load the results to your local image store, you can export the build results to the build cache only:

$ docker buildx build --builder cloud-<ORG>-<BUILDER_NAME> \
  --platform linux/amd64,linux/arm64 \
  --tag <IMAGE> \
  --output type=cacheonly .

Multi-platform builds

To run multi-platform builds, you must specify all of the platforms that you want to build for using the --platform flag.

$ docker buildx build --builder cloud-<ORG>-<BUILDER_NAME> \
  --platform linux/amd64,linux/arm64 \
  --tag <IMAGE> \
  --push .

If you don't specify the platform, the cloud builder automatically builds for the architecture matching your local environment.

To learn more about building for multiple platforms, refer to Multi-platform builds.

Cloud builds in Docker Desktop

The Docker Desktop Builds view works with Docker Build Cloud out of the box. This view can show information about not only your own builds, but also builds initiated by your team members using the same builder.

Teams using a shared builder get access to information such as:

• Ongoing and completed builds
• Build configuration, statistics, dependencies, and results
• Build source (Dockerfile)
• Build logs and errors

This lets you and your team work collaboratively on troubleshooting and improving build speeds, without having to send build logs and benchmarks back and forth between each other.

Use secrets with Docker Build Cloud

To use build secrets with Docker Build Cloud, such as authentication credentials or tokens, use the --secret and --ssh CLI flags for the docker buildx command. The traffic is encrypted and secrets are never stored in the build cache.

警告

If you're misusing build arguments to pass credentials, authentication tokens, or other secrets, you should refactor your build to pass the secrets using secret mounts instead. Build arguments are stored in the cache and their values are exposed through attestations. Secret mounts don't leak outside of the build and are never included in attestations.

For more information, refer to:

• docker buildx build --secret
• docker buildx build --ssh

Managing build cache

You don't need to manage Docker Build Cloud cache manually. The system manages it for you through garbage collection.

Old cache is automatically removed if you hit your storage limit. You can check your current cache state using the docker buildx du command.

To clear the builder's cache manually, use the docker buildx prune command. This works like pruning the cache for any other builder.

警告

Pruning a cloud builder's cache also removes the cache for other team members using the same builder.

Unset Docker Build Cloud as the default builder

If you've set a cloud builder as the default builder and want to revert to the default docker builder, run the following command:

$ docker context use default

This doesn't remove the builder from your system. It only changes the builder that's automatically selected to run your builds.

Registries on internal networks

It isn't possible to use Docker Build Cloud with a private registry or registry mirror on an internal network behind a VPN. All endpoints that a cloud builder interacts with, including OCI registries, must be accessible over the internet.

Interested in trying out an experimental feature?

We are currently testing an experimental feature which lets cloud builders access internal resources.

If you're interested in trying this feature, contact us using the Support form.