Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
Managing multiple Kubernetes clusters has long been a source of operational headaches and budget concerns for organizations running container infrastructure at scale. Red Hat’s OpenShift Hosted Control Planes (HCP) architecture provides a practical solution to these challenges by fundamentally rethinking how OpenShift control planes are deployed and managed.
The Traditional Control Plane Problem
In conventional Kubernetes deployments, every cluster requires three dedicated master nodes to run control plane components. These nodes host the API server, scheduler, controller manager, and etcd database. While this standalone model provides complete isolation and works well for single clusters, it creates significant inefficiencies when organizations need to manage dozens or hundreds of clusters.
Each set of master nodes consumes substantial resources: CPU, memory, and storage, regardless of actual workload demands. A control plane might use only 20-30% of its allocated resources during normal operations, yet those resources remain reserved and unavailable for other purposes. For organizations running 50 clusters, that means 150 master nodes sitting partially idle, burning through budget allocations and data center capacity.
The overhead extends beyond raw infrastructure costs. Every cluster requires individual monitoring, logging, security patches, and version upgrades. Operations teams find themselves managing infrastructure instead of supporting application teams. Provisioning new clusters becomes a lengthy process, often taking 30-45 minutes just to bootstrap the control plane infrastructure.
How Hosted Control Planes Change the Architecture
OpenShift HCP takes a different approach by decoupling the control plane from worker nodes. Instead of running on dedicated masters, control plane components run as regular pods within a management cluster. Each hosted cluster’s control plane lives in its own namespace, maintaining isolation while sharing the underlying infrastructure.
This architecture leverages the HyperShift project, which implements the necessary operators and APIs to manage these hosted control planes. The management cluster runs the HyperShift operator, which creates and manages HostedCluster and NodePool resources. A HostedCluster encapsulates the control plane configuration, while NodePools represent scalable sets of worker nodes that handle actual application workloads.
From a technical perspective, this means the API server, scheduler, and controller manager run as deployments within the management cluster. The etcd database runs as a StatefulSet, ensuring data persistence. Worker nodes connect to their control plane through a secure tunnel, unaware that their control plane isn’t running on dedicated infrastructure.
Resource Efficiency and Cost Reduction
The economic impact of HCP becomes clear when you examine resource utilization. Internal Red Hat analysis shows that hosted control planes can reduce total cost of ownership in key areas: over 60% savings in developer productivity, 65% reduction in operational costs for SRE teams, more than 50% savings in energy and facility costs, and depreciation cost reductions exceeding 90% Unlocking new possibilities: The general availability of hosted control planes for self-managed Red Hat OpenShift.
Consider a practical example: An organization running 20 production clusters traditionally needs 60 master nodes. With HCP, those same 20 control planes might run comfortably on a 6-node management cluster, depending on workload requirements. The resource consolidation is dramatic, you’re potentially reducing your control plane footprint by 90%.
When using ARM-based instances on AWS, hosted control planes can reduce costs by approximately 20% compared to equivalent x86 configurations A Guide to reducing OpenShift Costs with Arm Hosted Control Planes on AWS, adding another dimension to potential savings. The ability to mix architectures, running ARM management clusters with x86 worker nodes, or vice versa, provides flexibility in optimizing costs based on workload requirements.
Operational Benefits Beyond Cost
The advantages extend well beyond infrastructure savings. Cluster provisioning times drop significantly, a complete hosted cluster can be provisioned in 13 minutes, including nodepool virtual machine provisioning on OpenShift Virtualization Gain confidence with hosted control planes and OpenShift Virtualization using public cloud | Red Hat Developer. This rapid deployment enables teams to create ephemeral environments for testing, spin up clusters for specific projects, and respond quickly to changing business needs.
Version management becomes significantly more flexible. Control planes and worker nodes can run different OpenShift versions, allowing administrators to upgrade components independently. You might upgrade control planes during a maintenance window while keeping worker nodes stable, then upgrade workers in a rolling fashion without control plane disruption. This decoupling reduces risk and provides more upgrade flexibility.
Security boundaries strengthen with HCP. Since control planes run in isolated namespaces on the management cluster, credentials and secrets remain separated from workload environments. Infrastructure administrators working on the management cluster can’t accidentally impact worker node infrastructure, and compromised worker nodes can’t access control plane secrets.
The multi-tenancy story improves significantly. Each hosted cluster can map to different cloud accounts, projects, or network segments while sharing the same management infrastructure. For service providers or large enterprises with multiple business units, this enables efficient cluster-as-a-service offerings without the traditional infrastructure overhead.
Platform Support and Implementation Options
HCP supports multiple deployment targets, each suited to different scenarios. For public cloud deployments, ROSA with HCP became generally available in January 2024, offering clusters with control planes hosted in Red Hat-managed AWS accounts ROSA with hosted control planes (HCP) is generally available. This managed service approach removes control plane infrastructure from customer accounts entirely.
On-premises deployments leverage OpenShift Virtualization (using KubeVirt) or bare metal through the Agent provider. The OpenShift Virtualization approach is particularly interesting for organizations with existing virtualization infrastructure, as it allows running worker nodes as virtual machines managed through standard Kubernetes APIs.
With OpenShift 4.17, HCP support expanded to OpenStack environments as a developer preview Simplifying and optimizing Red Hat OpenShift on OpenStack with hosted control planes, enabling cloud service providers to offer efficient multi-tenant OpenShift clusters on their OpenStack infrastructure.
Real-World Deployment Considerations
Before adopting HCP, consider your specific requirements. The architecture works best when you need multiple clusters with similar configurations. If you’re running just one or two production clusters, the overhead of maintaining a management cluster might not justify the benefits.
Network architecture requires careful planning. Worker nodes need reliable connectivity to the management cluster hosting their control plane. Latency between sites becomes a factor for geographically distributed deployments. Plan for adequate bandwidth and consider network failure scenarios.
The management cluster becomes a critical component requiring high availability. While this consolidation improves overall efficiency, it also creates a single point of failure for multiple hosted clusters. Design your management cluster with appropriate redundancy, backup strategies, and disaster recovery plans.
Existing tools and processes might need adjustment. Monitoring and logging strategies that assume access to master nodes need reconfiguration. Backup procedures must account for the new architecture. Team responsibilities might shift as infrastructure management consolidates.
Getting Started with HCP
Organizations interested in HCP should start with proof-of-concept deployments. The multicluster engine operator (version 2.0 or later) provides the necessary components for self-managed deployments. For AWS environments, ROSA with HCP offers a managed service option that removes much of the operational complexity.
Begin by identifying candidate clusters for migration—development and test environments often make good starting points. These environments benefit from rapid provisioning and can tolerate the learning curve associated with new architecture patterns. As teams gain experience, production workloads can gradually migrate to the HCP model.
The Path Forward
OpenShift Hosted Control Planes represent a natural evolution in Kubernetes architecture, acknowledging that not every cluster needs dedicated control plane infrastructure. For organizations managing multiple clusters, the benefits, reduced costs, faster provisioning, improved security boundaries, and operational efficiency, make HCP worth serious consideration.
The technology has matured through deployments with major cloud providers and is now reaching broader availability across different platforms. As container orchestration becomes standard infrastructure, efficient multi-cluster management becomes essential. HCP provides a proven path to that efficiency, allowing teams to focus on delivering value through applications rather than managing cluster infrastructure.
Want to learn more on HCP, check out these other websites and resources:
Start with the Basics – What Are Hosted Control Planes
- https://www.redhat.com/en/topics/containers/what-are-hosted-control-planes
- Perfect starting point for teams evaluating HCP – covers core concepts, benefits, and use cases with both self-managed and ROSA options
Hands-On Learning – ROSA with Hosted Control Planes Experience
- https://developers.redhat.com/products/redhat-openshift-service-aws/overview
- Get practical experience with HCP through Red Hat’s free hands-on labs – ideal for proof-of-concept testing without infrastructure investment
Technical Documentation – OpenShift Hosted Control Planes Guide
- https://docs.redhat.com/en/documentation/openshift_container_platform/4.14/html/hosted_control_planes/index
- Comprehensive implementation guide for architects and administrators planning self-managed HCP deployments