Docker v29.2.0-rc.1: Experimental NRI and gRPC Support

For developers and administrators evaluating the latest container innovations, the docker 29.2.0-rc.1 release notes detail a significant pre-release candidate shipped on December 17, 2025. This update introduces experimental Node Resource Interface (NRI) support, a major feature that allows external resource management plugins to dynamically adjust container CPU, memory, and I/O allocations without requiring container restarts. Alongside this, the release adds native gRPC support on the Docker Engine’s listening socket, enabling more efficient API communication for modern tooling. The underlying BuildKit component has been updated to version 0.26.3, bringing performance improvements and bug fixes for image builds. This release candidate is a testing ground for new integration capabilities, particularly for teams looking to implement advanced, dynamic resource management strategies.

This release candidate introduces experimental features and component updates for testing and evaluation. This pre-release is recommended for DevOps engineers and API developers working in non-production environments who want to explore dynamic resource management and modern API protocols. Users should upgrade to evaluate the new NRI and gRPC capabilities for future integration planning, but should not deploy this version in production systems.

What Changed

• Experimental NRI Support: Added Node Resource Interface support, enabling external plugins to dynamically manage container resources. The docker info command now includes an NRI section displaying plugin status.
• BuildKit Update: Updated BuildKit to version 0.26.3, which includes performance improvements and bug fixes for container image builds.
• gRPC API Support: Added native gRPC protocol support on the Docker Engine listening socket, allowing tools to communicate using gRPC alongside the existing REST API.
• Rootless CDI Path Expansion: Enhanced rootless Container Device Interface compatibility by considering $XDG_CONFIG_HOME/cdi and $XDG_RUNTIME_DIR/cdi paths when looking for CDI devices.

Why It Matters

• The experimental NRI support opens the door to more sophisticated container orchestration, where third-party plugins can adjust resources in real-time based on workload demands, potentially improving cluster efficiency.
• Native gRPC support modernizes how tools interact with Docker Engine, offering a more efficient, streaming-friendly protocol that’s becoming standard in cloud-native ecosystems.
• The BuildKit update delivers tangible performance gains for developers building container images, reducing wait times in CI/CD pipelines.
• Rootless CDI path improvements enhance security and usability for users running Docker without root privileges, ensuring better compatibility with standard Linux directory conventions.

Who Should Upgrade

This release is particularly relevant for DevOps engineers and system administrators who manage containerized workloads and want to test dynamic resource allocation strategies. API developers building integrations with Docker Engine should evaluate the new gRPC support for potential performance benefits. Infrastructure teams planning future container management enhancements should examine the NRI capabilities in development environments. This release candidate is not intended for production use but serves as an important testing milestone for these advanced features.

How to Upgrade

1. Backup current Docker configurations, container states, and important data.
2. Review the experimental NRI documentation to understand compatibility requirements and plugin architecture.
3. Run docker version to verify your current installation details.
4. Follow Docker’s official release candidate installation instructions for your specific platform (Linux, macOS, or Windows).
5. Test NRI functionality with sample plugins in a controlled development or staging environment.
6. Validate existing workflows and tools that might use gRPC communication with the Docker Engine.

Usage Examples

• Configuring NRI plugins to automatically adjust container CPU limits when batch processing jobs spike in resource consumption, optimizing cluster utilization.
• Using the updated docker info command to monitor the NRI section, checking plugin health and viewing real-time resource adjustment statistics.
• Implementing custom gRPC clients to communicate with Docker Engine for monitoring or automation tasks, taking advantage of the protocol’s efficiency for streaming data.

Known Issues

• This is a release candidate (rc.1) not intended for production deployment or critical workloads.
• The experimental NRI feature may have stability issues and could undergo significant API changes in future releases.
• No specific security fixes or critical bug patches are mentioned in these docker 29.2.0-rc.1 release notes, so evaluate accordingly.

Feature Flow

Official Release Notes

View full release notes on GitHub →