OpenShift vs Kubernetes on Bare Metal: Which One to Choose

Container orchestration platforms run differently on bare metal servers than on virtualized infrastructure. Users often run Kubernetes and OpenShift on physical hardware. This setup cuts out hypervisor overhead and gives direct access to server resources. It also improves performance for containerized workloads needing steady latency and fast speeds.

This guide compares Kubernetes and OpenShift specifically for bare metal deployments. You will learn what makes each platform different, how they perform, and what they need to operate. We also look at real-world deployment scenarios that will help you choose the best orchestration platform for your bare metal infrastructure.

#What is Kubernetes on bare metal?

Kubernetes on bare metal is a platform for container orchestration. It is installed directly on physical servers, without using any virtualization layer. The Kubernetes control plane and worker nodes operate on the host operating system.

This system boots straight from the server's hardware. This deployment method allows containers to access CPU, memory, storage, and network resources directly through the Linux kernel. This removes the performance overhead caused by hypervisors.

The core Kubernetes architecture includes control plane nodes and worker nodes. Control plane components manage the cluster state, schedule containers, and handle API requests. Worker nodes run container workloads with a runtime like containerd or CRI-O. On bare metal servers, they make full use of the physical hardware without a hypervisor.

Network plugins create virtual networks between containers across physical servers. Moreover, storage drivers connect containers to local NVMe drives or network-attached storage systems. The kubelet agent on each node manages container lifecycles and reports resource usage directly from hardware counters.

You can install Kubernetes on bare metal using several methods:

• kubeadm: Official tool that automates cluster bootstrapping
• kubespray: Ansible playbooks for production-grade deployments
• Manual deployment: Direct binary deployment for maximum control
• RKE2: Rancher's security-focused Kubernetes distribution
• K3s: Lightweight option for edge deployments

For each installation method, you need to configure the operating system, network settings, and storage drivers based on your hardware. System administrators must handle tasks like tuning kernel settings and installing drivers. These tasks are usually handled by cloud providers.

#What is OpenShift on bare metal?

OpenShift on bare metal is Red Hat's enterprise Kubernetes platform. It runs directly on physical servers. This setup offers an integrated container platform. It also includes developer tools, security features, and operational capabilities.

OpenShift is different from vanilla Kubernetes. It offers a full application platform. This includes automated deployment, built-in monitoring, CI/CD pipelines, and enterprise support. It also runs on dedicated hardware, so there’s no virtualization overhead.

Red Hat CoreOS (RHCOS) serves as the default operating system for OpenShift nodes. RHCOS uses an immutable filesystem design where the OS image updates atomically. This approach reduces configuration drift and simplifies node management across large bare metal clusters.

Compared to traditional Linux distributions, RHCOS reduces attack surface through its minimal, container-optimized design.

OpenShift offers two deployment paths for bare metal:

• Installer-Provisioned Infrastructure (IPI): Automated deployment using Ironic for bare metal provisioning
• User-Provisioned Infrastructure (UPI): Manual deployment with full control over infrastructure

The IPI method orchestrates BIOS configuration, OS installation, and cluster bootstrapping. Users provide BMC credentials and network details, then OpenShift handles the complete deployment process. UPI deployments give administrators control over each step but require more expertise and time. OpenShift includes integrated components that Kubernetes leaves to operators:

• Container image registry with scanning capabilities
• Router for ingress traffic management
• Monitoring stack with Prometheus and Grafana
• Logging aggregation with Elasticsearch
• Web console for cluster management
• CI/CD pipelines with Tekton

These built-in features use more CPU and memory than basic Kubernetes setups. An OpenShift control plane usually needs at least 16GB of RAM. In contrast, Kubernetes can operate with just 8GB.

#OpenShift vs Kubernetes on bare metal

Running these platforms on bare metal servers shows clear differences. Without virtualization, you manage the hardware directly. This makes choosing the right platform important for your team's success.

This section looks at what makes each platform different on bare metal: how hard they are to install, how much resources they use, their security features, and how updates work. These differences affect your costs and what skills your team needs.

#Key technical differences on bare metal

Let’s explore some of the major differences between OpenShift and Kubernetes on bare metal.

#Installation and setup complexity

Kubernetes installation on bare metal requires manual configuration of numerous components. The official documentation lists over 50 configuration parameters for production deployments. The process typically takes 4-8 hours and includes:

• Installing container runtimes (containerd or CRI-O)
• Configuring systemd units for each component
• Setting up etcd clusters for state management
• Initializing the control plane with kubeadm
• Selecting and configuring CNI plugins for networking
• Managing IP address allocation across nodes

OpenShift orchestrates most deployment tasks through its installer. The automated process takes 45-90 minutes and requires only:

• A configuration file with cluster specifications
• BMC credentials for server access
• Network details for the cluster

The installer then automatically discovers servers, installs RHCOS, and provisions all components.

Flexibility vs Consistency

Manual Kubernetes installation provides complete flexibility:

• Choose specific etcd versions
• Set custom API server flags
• Integrate existing monitoring systems
• Configure every component to your needs

OpenShift's opinionated installation ensures consistency but limits initial customization:

• Uses predetermined component versions
• Follows Red Hat's best practices
• Allows customization after deployment
• Reduces configuration errors

#Operating system requirements

Kubernetes runs on virtually any Linux distribution that supports modern container runtimes. Some of these distributions include:

• Ubuntu 22.04/24.04 LTS
• Debian 11/12
• CentOS Stream 8/9
• SUSE Linux Enterprise
• Amazon Linux 2

This flexibility allows organizations to use existing OS expertise and tooling. System administrators can apply familiar hardening procedures and compliance configurations. Additionally, package management uses standard distribution tools like apt or yum.

OpenShift requires RHCOS for control plane nodes and strongly recommends it for workers. RHCOS design documentation highlights these features:

• Immutable root filesystem
• Automatic updates through OpenShift
• SELinux enforcement by default
• Integrated with OpenShift Machine Config Operator
• Optimized for container workloads

Organizations needing specific drivers or applications can use RHEL for worker nodes. However, this split configuration increases operational complexity. RHCOS nodes update automatically while RHEL nodes require manual patching.

#Networking implementation

Kubernetes supports multiple Container Network Interface (CNI) plugins, each with different performance characteristics on bare metal. Here are some approximate benchmarks:

Bare metal deployments can use SR-IOV for direct network card access, achieving near line-rate performance. BGP integration enables direct route advertisement to the physical network infrastructure.

OpenShift includes OpenShift SDN and OVN-Kubernetes as supported network plugins. However, OVN-Kubernetes delivers better throughput than OpenShift SDN. Both provide:

• Integrated network policy enforcement
• Multi-tenancy with project isolation
• Egress IP assignment
• Automatic DNS configuration

OVN-Kubernetes replaces OpenShift SDN in newer versions, offering better performance through hardware offload support. Network configuration happens through OpenShift resources rather than CNI configuration files.

#Storage solutions

Kubernetes storage depends on Container Storage Interface (CSI) drivers for persistent volumes. The CSI documentation lists over 100 certified drivers. Common bare metal storage options include:

• Local storage: Direct access to NVMe or SSD drives
• NFS: Shared filesystem for multi-node access
• Ceph: Distributed storage across nodes
• iSCSI: Block storage from SAN systems

Administrators must install and provision CSI drivers separately. Local storage provides the best performance but lacks redundancy. Moreover, distributed storage solutions require additional planning for bare metal nodes.

OpenShift includes the Local Storage Operator for bare metal deployments. OpenShift documentation shows the operator:

• Discovers local disks automatically
• Creates persistent volumes from selected devices
• Manages device lifecycle and cleanup
• Integrates with OpenShift storage classes

Additional operators provide Ceph (OpenShift Data Foundation) and NFS provisioning. The integrated approach simplifies storage configuration but requires learning OpenShift-specific concepts.

#Security features

Kubernetes provides fundamental security features outlined in the official security documentation:

• Role-Based Access Control (RBAC)
• Network policies for traffic control
• Pod Security Standards
• Secret management
• Audit logging

Bare metal deployments must implement additional security layers. Organizations configure firewall rules, SELinux policies, and kernel security modules manually. Also, security scanning requires third-party tools integration.

To strengthen security, OpenShift introduces several enterprise-grade features. According to Red Hat, these reduce incidents by 45%:

• Security Context Constraints (SCC) for pod permissions
• Compliance scanning with the Compliance Operator
• File integrity monitoring
• Network traffic encryption by default

These features activate automatically during deployment. OpenShift's approach reduces security configuration errors but requires understanding Red Hat's security model.

#Performance considerations on bare metal

Performance differences between Kubernetes and OpenShift on bare metal stem from architectural choices and included components. Direct hardware access amplifies these differences compared to virtualized deployments.

#Resource overhead

OpenShift's additional components consume more resources than vanilla Kubernetes:

Kubernetes allows minimal deployments where every megabyte matters. Edge locations and cost-sensitive environments benefit from lower resource requirements. OpenShift's overhead provides value through integrated features, but requires larger bare metal servers.

#Network performance

Latency measurements favor minimal network stacks. Kubernetes with SR-IOV achieves sub-100 microsecond latency for pod-to-pod communication. OpenShift adds 10-20 microseconds due to additional network services.

#Storage performance

Direct NVMe access on bare metal servers delivers exceptional storage performance. Storage benchmarking with fio shows:

• Local NVMe raw performance: 500,000 IOPS
• Kubernetes local PV: 490,000 IOPS (2% overhead)
• OpenShift local storage: 475,000 IOPS (5% overhead)

The performance difference comes from additional abstraction layers and monitoring in OpenShift. Write-intensive workloads like databases notice the difference more than read-heavy applications.

#Operational aspects

Daily operations differ significantly between platforms, especially on bare metal, where administrators handle all infrastructure tasks. CNCF's survey data indicates that 68% of organizations cite operational complexity as their primary Kubernetes challenge.

#Management and monitoring

Kubernetes requires assembling a monitoring stack from separate components. The Kubernetes SIG-Instrumentation recommends:

• Prometheus for metrics collection
• Grafana for visualization
• Elasticsearch for log aggregation
• Jaeger for distributed tracing

Installation and configuration take additional time. Also, integration requires understanding each tool's configuration format. Bare metal deployments need node-level monitoring for hardware health. OpenShift includes integrated monitoring and logging based on OpenShift's monitoring architecture:

• Pre-configured Prometheus and Alertmanager
• Grafana dashboards for cluster metrics
• Elasticsearch, Fluentd, and Kibana for logging
• Web console with real-time cluster status

The integrated stack starts working immediately after deployment. However, customization requires understanding OpenShift's operator model and custom resources.

#Updates and maintenance

Kubernetes updates require careful planning on bare metal. The Kubernetes version skew policy mandates specific compatibility requirements:

1. Backup etcd data
2. Upgrade control plane components
3. Update worker nodes individually
4. Verify component compatibility
5. Test application functionality

The process requires 2-4 hours of maintenance windows. Version skew between components can cause issues. Hence, bare metal nodes need firmware updates coordinated with Kubernetes upgrades.

OpenShift orchestrates cluster updates through the Machine Config Operator:

1. The administrator selects the target version
2. Platform updates the control plane
3. Worker nodes update based on the machine config
4. Automatic health checks between steps

Updates are complete without manual intervention in most cases. RHCOS nodes receive OS updates through the same mechanism. However, problems during updates can be harder to debug due to automation complexity.

#Support and documentation

Kubernetes relies on community support and documentation. GitHub statistics show over 3,000 contributors and 2,000+ active issues. Enterprise support comes from third-party vendors or consultants. Quality varies between providers. Bare metal-specific documentation is limited.

On the other hand, OpenShift provides enterprise support through Red Hat. Support costs form part of the OpenShift subscription. Red Hat's bare metal expertise helps with hardware-specific issues.

#Cost analysis

Total cost of ownership extends beyond software licensing to include hardware, operations, and opportunity costs.

#Licensing costs

Kubernetes costs nothing for the software itself. Organizations pay for:

• Hardware or hosting costs
• Support contracts (optional)
• Additional tool licenses
• Training and certification

A 10-node bare metal Kubernetes cluster incurs no software licensing fees. The budget goes entirely to hardware and operational expenses.

OpenShift requires subscriptions based on core pairs. Red Hat's pricing model shows:

• Standard subscription: $15,000-20,000 per 64 cores annually
• Premium subscription: $23,000-30,000 per 64 cores annually
• Pricing includes support and all platform features

A 10-node cluster with 16-core servers costs approximately $40,000-60,000 annually in OpenShift licenses.

#Operational costs

Kubernetes operational costs include higher administrative overhead, such as:

• Higher administrator time for setup (40-80 hours initial)
• Ongoing maintenance (10-20 hours monthly)
• Tool integration effort
• Security patching time

Organizations need Kubernetes expertise for effective operations. However, OpenShift reduces operational time through automation:

• Automated deployment (8-16 hours initial)
• Lower maintenance (5-10 hours monthly)
• Integrated tooling saves integration effort
• Automated updates reduce patching time

The subscription cost often balances against reduced operational expenses. Organizations with limited staff benefit from OpenShift's automation.

#Use case scenarios

Now, let’s explore some use case scenarios.

#When to choose Kubernetes on bare metal

Cost-sensitive deployments favor vanilla Kubernetes. A machine learning startup running GPU workloads saves $100,000+ annually using Kubernetes instead of OpenShift.

Organizations with existing Kubernetes expertise deploy faster with familiar tools. Teams already running Kubernetes in cloud environments apply the same knowledge to bare metal deployments. Custom automation and GitOps workflows transfer directly.

Additionally, maximum flexibility requirements suit Kubernetes deployments. High-frequency trading firms achieve sub-microsecond latency with custom kernel parameters and network configurations. Kubernetes allows complete control over every component. Moreover, custom CNI plugins enable proprietary network protocols.

Specific workload examples for Kubernetes on bare metal include:

• High-frequency trading systems that require kernel bypass networking
• Edge computing with minimal resource footprint
• Research clusters with specialized hardware
• Multi-cloud deployments with consistent tooling

#When to choose OpenShift on bare metal

Enterprise compliance requirements often mandate OpenShift's integrated security features. PCI Security Standards Council guidance specifically mentions container platform security requirements that OpenShift addresses natively.

Financial services companies meet regulatory requirements faster with OpenShift's compliance operators. Healthcare organizations also benefit from automated security scanning and audit trails. Integrated CI/CD needs favor OpenShift's built-in pipelines. Development teams start building applications immediately without assembling separate tools.

Furthermore, multi-tenancy scenarios work better with OpenShift's project isolation. Service providers hosting multiple customers need strong separation between workloads. OpenShift's network policies and resource quotas enforce boundaries automatically. Specific workload examples for OpenShift on bare metal:

• Multi-tenant SaaS platforms with compliance requirements
• Enterprise application modernization projects
• Government systems that require security certifications
• Large-scale IoT data processing with integrated analytics

#Conclusion

Kubernetes and OpenShift serve different needs on bare metal infrastructure. Kubernetes provides flexibility and cost savings for organizations with technical expertise. OpenShift delivers integrated features and enterprise support at a higher cost.

Choose Kubernetes when you need maximum control, have budget constraints, or run specialized workloads. Select OpenShift for enterprise deployments requiring compliance, integrated tools, and vendor support.

Bare metal servers provide the foundation for either platform. Cherry Servers offers flexible bare metal options with hourly billing for proof-of-concept deployments.