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v4.16 [February 2026]

Release Themes: Replication Scalability, Content Archive, Pipeline Control

Executive Summary

Digital Rebar v4.16 delivers significant advancements in performance, scalability, flexibility, and deployment capabilities, reinforcing its position as a robust, enterprise-grade bare metal automation platform.

This release introduces a modern Event-Router replacement. We have developed and deployed a streamlined event-router that deprecates the previous filebeat and auditor plugins. This upgrade significantly increases administrative observability and enhances customers' abilities to audit access controls

A new Content Archive capability arrives as a Tech Preview in v4.16 (with general availability targeted for v4.17). This feature streamlines the packaging, distribution, and lifecycle management of content packs, plugins, and third-party assets.

The Pipeline Control system is now fully implemented, giving customers greater control over specific pipeline elements. This foundational capability unlocks greater customization and sets the stage for expanded content integrations in future releases.

A major Manager Replication Refactoring addresses key scalability limitations encountered by large-scale enterprise deployments. The redesigned backend delivers improved robustness, performance, and support for significantly larger clusters. Complementary frontend improvements are planned for completion in version 4.17.

Eikon, the native image deployment engine positioned to replace Curtin, sees substantial maturation in this cycle. Key enhancements include a more universal pipeline that supports task injection and modification, consolidated Debian/RHEL GRUB handling, simplified raw image deployment, support for cloud images, multi-architecture machine deployments, and secure authentication (basic-auth and mTLS) for image downloads from local or remote repositories. These updates make Eikon more versatile and reliable for diverse provisioning scenarios.

Finally, OpenShift Support receives targeted enhancements through the OpenShift content pack, introducing automated Agent-Based Install sequencing for the bootstrap process, along with secure control-plane and worker node additions featuring automated CSR approval.

Overall, v4.16 strengthens Digital Rebar's core infrastructure for demanding production environments, with a clear focus on reliability, scale, and streamlined operations -- paving the way for even broader enterprise adoption.

Important Notices

Note

Release Information

New for this release:

See other release notes for previous Release Information. All the incremental fixes to previous releases. See Change History

Vulnerabilities

Golang Updates

In order to reduce and attempt to prevent supply-chain attacks, RackN watches that golang security streams and updates the components that have issues. This release continues those updates.

Deprecations

Bootenv Deprecation

Many of the bootenvs that are provided in the various content packs are being marked as deprecated and will be removed in a future release.

These deprecations are based upon unsupported minor releases or end-of-life statements by the vendors.

These include:

  • VMWare
  • Debian
  • Ubuntu
  • Redhat OS families (RHEL, Centos, Fedora)
  • Alma
  • Rocky

The bootenvs are annotated in their documentation and descriptions. See more information at RackN Provided Bootenv Lifecycle.

Image-deploy plugin

While not deprecated in th release, the image-deploy plugin will eventually be deprecated by eikon. Users should plan to explore the new functions of eikon while planning removal of image-deploy. RackN is looking for feedback on usage and issues. It is likely to be removed as the default imager in v4.17.

Removals

None known

FEATURES

Event Router

Digital Rebar v4.16 introduces a modern and streamlined native event-router that deprecates the previous filebeat and auditor plugin architecture. This upgrade dramatically increases administrative observability by delivering deeper, more integrated visibility into system events and operations. It also significantly enhances customers' ability to audit access controls, providing stronger governance, compliance tracking, and security posture for enterprise deployments. At the same time, the streamlined native implementation markedly improves overall event handling efficiency, system performance, and reliability compared with the legacy approach.

This combination of enhanced observability, superior auditing capabilities, and a more robust and performant foundation makes the new event-router a critical upgrade for organizations that require both high-fidelity monitoring and dependable, large-scale automation operations.

More information at Event Router.

Content Archive

A new packaging format called Content Archive has been introduced in Digital Rebar Provision v4.16 as a Technical Preview. General availability is planned for the v4.17 release.

Content Archives offer several key advantages over traditional content delivery methods:

  • Simplified packaging and distribution — Archives are self-contained, bundling everything required for operation:

    • Standard object definitions (as found in regular content bundles)
    • All necessary artifacts (raw files, auxiliary executables, third-party tools)
    • Extensions provided by plugin developers to enhance dr-provision capabilities

  • Atomic, multi-archive upgrades — You can stage multiple Content Archives simultaneously and then apply them in a single atomic commit operation, ensuring consistent and reliable upgrades across your environment.

  • Lower disk space usage — By leveraging dr-provision's ability to mount various file types directly as filesystems, Content Archives minimize the number of physical files stored on disk. This reduces (and in many cases eliminates) the overhead of manually ensuring all required files are present and correctly managed.

In v4.16, operators can create and manage Content Archives using the drpcli content-archive commands.

Note

Full integration with the Content Catalog, UX interface, and Manager tools is targeted for completion in the v4.17 development cycle.

Pipeline Control

The Pipeline Control system is now more flexible, empowering customers with greater control over specific task configuration options such as turning off hardware elements, skipping operating system installation, and preserving data drives during rebuild. This lays a strong foundation for ongoing expansion, with additional content integrations planned to further enhance its value.

Manager Replication Refactorying

A major Manager Replication Refactoring has been completed in v4.16, directly addressing scalability challenges for our largest enterprise customers. The core backend redesign delivers substantially improved robustness, performance, and support for significantly larger and more distributed deployments.

Key enhancements include splitting Single Pane and Version Set replication into independent modes. These can now be enabled, disabled, and operated separately, allowing organizations to eliminate unnecessary replication overhead by tailoring replication to their specific hierarchy needs.

  • Version Set replication handles content (such as content packs, plugins, and version-controlled assets) from upstream to downstream managers—ideal for centralized content distribution without propagating operational data.
  • Single Pane replication manages database objects (such as machines, workflows, and other runtime state) from downstream to upstream managers—enabling aggregated visibility and control without replicating bulk content.

This granular control enables hierarchies to replicate only the data types required (e.g., content-only for distributed edge sites or database objects-only for centralized monitoring), reducing network and processing load while maintaining flexibility.

Eikon Improvements

Throughout the release cycle, Eikon has received numerous updates and enhancements as it moves to replace Curtin. Additional information is available in Eikon Image Deploy and Eikon Architecture.

Major improvements to Eikon include:

  • Tasks moved to eikon-image-deploy pipeline allowing more flexible task injection
  • Consolidated Debian/RHEL grub tasks
  • Simplified raw image deployment
  • Cloud Image support
  • Deploy images to several machine architectures
  • Authentication using basic-auth and mTLS for downloading images from local or remote repositories

OpenShift Enhancements

The OpenShift content pack now provides an Openshift Agent Based Install that will automatically sequence the bootstrap process. Secure control-plane and worker additions are now supported with automated CSR approval.

Other Items of Note

Bug Fixes abd Minor Improvements

Most if not all bug fixes have been rolled into the v4.15 release stream and can be seen in aach component's changes. See Change History for more details.