Red Hat OpenShift 4.18: Enhanced Virtualization and New Features

Red Hat has released OpenShift Container Platform 4.18, bringing a wave of improvements to its hybrid cloud Kubernetes platform. This release is based on Kubernetes 1.31 (with CRI-O 1.31) and focuses on core platform enhancements and deeper integration of virtualization capabilities. In addition to bolstering security and management (like better handling of secrets and certificates), OpenShift 4.18 delivers significant new features for OpenShift Virtualization – Red Hat’s solution for running virtual machines (VMs) on OpenShift. Below, I have highlighted the general updates in OpenShift 4.18, before then diving into the virtualization enhancements, explaining how they benefit virtualization admins, teams and enterprises.

General Updates in OpenShift 4.18

• Platform & Security Foundations: OpenShift 4.18 upgrades the underlying Kubernetes to v1.31 and introduces improvements in secrets and certificate management. For example, the Secrets Store CSI Driver operator is now generally available, allowing OpenShift workloads to fetch secrets from external vaults without storing them on-cluster. This enhances security by making the cluster “unaware” of secret data, which is ideal for regulated environments.

• Simplified TLS Certificate Management: This release also expands cert-manager integration. OpenShift 4.18 includes cert-manager v1.15 (as an operator) and even a tech preview of istio-csr for Service Mesh, so platform and service mesh components can automatically get certificates from a central source. By extending cert-manager’s reach to more OpenShift components (ingress, API server, service mesh), enterprises can more easily centralize TLS certificate handling, reducing the manual effort of managing multiple certificate authorities across clusters.

• Networking Enhancements (UDN & BGP): A major networking feature – User Defined Networks (UDNs) – graduates to general availability in 4.18. UDNs let admins create custom Layer-2 or Layer-3 network segments in OpenShift, bringing data center networking concepts (like VLANs or tenant networks) into Kubernetes. This improves network flexibility and segmentation by enabling isolated networks or overlapping subnets for different teams/projects. Notably, UDNs work for both pods and virtual machines as primary or secondary interfaces, which is key for VM use cases (providing VMs with stable, static IPs and live migration-friendly networks). OpenShift 4.18 also integrates Border Gateway Protocol (BGP) routing into OVN-Kubernetes for UDN networks. With BGP, cluster networks can dynamically advertise routes to external routers and learn routes, simplifying integration with existing data center networks or third-party load balancers.

• Multi-Cluster Infrastructure: For virtualization on vSphere, OpenShift 4.18 adds support to deploy a single OpenShift cluster across multiple vSphere vCenter clusters, without needing shared storage . This improves high availability and scalability on VMware infrastructure by allowing multiple independent vCenter domains to host one OpenShift cluster (configured at install time). On the disconnected-install side, the oc-mirror v2 plugin is now GA with substantial performance boosts . Administrators mirroring OpenShift images to a private registry will see faster mirror creation, caching to avoid redundant downloads, better image pruning control, and even support for mirroring Helm charts . This greatly streamlines installing and updating OpenShift in offline or restricted environments.

• Operator Lifecycle Manager v1: OpenShift 4.18 debuts OLM v1 (the next-gen Operator Lifecycle Manager) as a stable, general availability feature. OLM v1 (formerly tech preview) modernizes how Operators are managed by simplifying APIs, enhancing security, and improving reliability of operator upgrades . This means cluster admins get a more robust and user-friendly experience when installing or upgrading Operators (the add-on services in OpenShift’s ecosystem).

• Cluster Hibernation Improvements: OpenShift 4.18 makes it easier to shut down clusters when not in use and bring them back later. Cluster control planes can now auto-recover from expired certificates after being hibernated for up to 90 days (previously 30 days) . In practice, this means you can suspend a non-production cluster (to save cloud costs, for example) and later revive it without an elaborate manual cert recovery process – simply approve the automated CertificateSigningRequests on restore. For single-node OpenShift (SNO) installations, you can even hibernate up to one year from install with one-click recovery . This enhancement reduces maintenance overhead and downtime when pausing clusters for extended periods.

OpenShift Virtualization 4.18 Enhancements

OpenShift 4.18 places a special emphasis on OpenShift Virtualization, aiming to make running VMs on OpenShift more powerful and easier to manage. The updates range from a new standalone virtualization edition to UI/UX improvements, networking, storage, and integration with tools for migration and backup. Here are the key virtualization-specific features and improvements introduced:

New OpenShift Virtualization Engine Edition

To encourage VM workload migration onto OpenShift, Red Hat introduced OpenShift Virtualization Engine, a new virtualization-only edition of OpenShift. This edition is focused purely on running and managing VMs (without containers) and offers a cost-effective path for organizations moving off traditional hypervisors . Each Virtualization Engine subscription covers up to 128 CPU cores of VM capacity, allowing enterprises to use dense hardware efficiently . OpenShift Virtualization Engine includes all core VM orchestration capabilities (built on the proven KVM hypervisor, managed by OpenShift) and can integrate with Red Hat’s management tools – for example, Advanced Cluster Management for Virtualization provides multi-cluster VM lifecycle management, and Ansible Automation can automate large-scale VM operations. This gives organizations a streamlined, future-proof environment for VMs, with the option to later upgrade to the full OpenShift platform when they’re ready to add containers.

Streamlined VM Management and UI

OpenShift Virtualization 4.18 includes several console UI enhancements to simplify day-to-day VM operations:

• Tree-View Navigation (Tech Preview): A new tree-view for virtual machines is introduced in tech preview. Instead of viewing a flat list of VMs per project, admins can see a hierarchical view and even create logical folders to group VMs (beyond just using namespaces). This makes it easier to organize and navigate large numbers of VMs – you can collapse/expand groups and quickly find a VM using the built-in search at the top of the tree.

• Bulk VM Actions: Managing multiple VMs is more efficient now. OpenShift 4.18 allows selecting multiple VMs in the web console and performing actions like start, stop, or restart on all of them at once. This “bulk action” capability saves time for administrators who need to, for example, power on a set of VMs or gracefully shut down a group during maintenance windows.

• Resource Usage at a Glance: The VM list view can be customized to show new resource utilization columns. By enabling these columns, admins can immediately see each VM’s CPU, memory, and storage consumption from the main list rather than having to inspect VMs one by one. This provides a quick way to identify resource hogs or to verify that VMs are within their allocated quotas.

These UI improvements enhance productivity by making the virtualization layer feel more integrated and manageable within OpenShift’s console, similar to how one would manage VMs in a traditional virtualization platform.

Advanced Networking for VMs

Networking capabilities for OpenShift Virtualization have expanded, aligning with the introduction of User Defined Networks:

• User-Defined Networks (UDN) for VMs: OpenShift 4.18 lets virtual machines attach to custom networks defined by UDNs on their primary interface. In practice, this means VM administrators can create tenant-specific L2 networks (with their own subnets or VLAN-like isolation) and assign VMs to those networks, just as they would in a conventional virtualization environment. UDNs support overlapping subnets and isolated segments per project or tenant, giving greater network segmentation in a multi-tenant cluster. For example, a VM can now have a static IP that it keeps for its lifetime – a common requirement in enterprise VM environments – and UDN ensures that the IP is consistently reachable, even during live migrations.

• Live Migration-Friendly Networking: Because UDN can provide a Layer-2 overlay network, VMs can be live-migrated between nodes without losing network connectivity. The UDN stays consistent across the cluster nodes, which is crucial for moving running VMs with minimal disruption. This bridges a gap for VM workloads on Kubernetes, making the experience closer to traditional hypervisors where migrating a VM retains its MAC/IP and network state.

• BGP for External Connectivity: On top of UDN, OpenShift 4.18 builds in support for BGP routing in the cluster network. This means that the routes to pod and VM networks can be advertised to external routers via BGP. Conversely, the cluster can learn external routes. For users, this enables advanced networking setups – for instance, integrating OpenShift workloads directly into data center networks or enabling external load balancers to reach VMs and pods without manual route configurations. Over time, Red Hat plans to extend this with EVPN for even more flexible network overlays between clusters, but already, the BGP integration in 4.18 is a big step towards seamless hybrid networking.

• Public Cloud and Hybrid Support: Recognizing that many run OpenShift on cloud platforms, 4.18 makes UDNs available in public cloud environments as well. You can use these primary tenant networks on AWS now (GA in 4.18) and even try OpenShift Virtualization on Oracle Cloud Infrastructure (OCI) bare metal (tech preview). In short, OpenShift’s VM networking enhancements work consistently, whether on-premises or in the cloud, so users get the same network customization and multi-network support for their VMs in any environment.

Storage Live Migration and Improvements

Managing VM storage is easier and more flexible in OpenShift 4.18:

• Live Storage Migration: A long-requested feature – migrating a VM’s disk volumes between storage classes – is now available. OpenShift Virtualization 4.18 supports storage live migration of VMs. This allows you to move a VM’s persistent volumes from one storage backend to another without shutting down the VM. For example, if you want to retire an old storage array or move a workload to a faster SSD-based storage class, you can migrate the disks while the VM continues to run. This capability is extremely useful for onboarding new storage, rebalancing usage, or performing infrastructure upgrades with zero downtime.

• Hotplug Disk Migration & Conversion: The storage migration feature isn’t limited to main disks – it also covers hot-plugged VM disks now, meaning even disks attached at runtime can be migrated to a new storage class. Additionally, OpenShift Virtualization will intelligently handle differences between storage types: if you migrate between a filesystem-based storage and a block storage class, the platform can convert the volume format (filesystem or block mode) as needed on the fly. The migration process will even suggest the optimal target configuration before you begin, so you get the best performance on the new storage.

• Performance and Efficiency: Under the hood, 4.18’s migration tool optimizes data transfer. It can detect sparsely-used space on disks and skip copying empty blocks, resulting in faster migrations for thin-provisioned volumes. After a migration, the system labels the migrated volumes to indicate their source, helping admins track which old storage can be reclaimed safely. All of this adds up to more efficient storage management – admins can maintain and upgrade storage infrastructure with minimal impact on running VM workloads.

Performance and Migration Enhancements

Moving VMs into OpenShift and running them at scale gets easier in this release:

• Migration Toolkit for Virtualization (MTV) Updates: Red Hat’s Migration Toolkit for Virtualization (which helps bulk-migrate VMs from traditional platforms like VMware or Hyper-V into OpenShift) received several upgrades in 4.18. First, migration plans can now specify custom PersistentVolumeClaim names for each migrated volume, giving more control over the target setup. More importantly, migration speeds have improved – 4.18 includes scheduler optimizations for both cold migrations (VMs powered off) and warm migrations (running VMs) that result in shorter migration windows. This means less downtime or faster cutovers when transferring hundreds or thousands of VMs. There’s also expanded support to migrate SUSE Linux VMs, broadening the range of source VMs that can be moved onto OpenShift. To make the whole process easier, the MTV documentation was restructured for better guidance, and Red Hat has published performance-tuning recommendations so customers can follow best practices for large-scale migrations.

• VM Workload Metrics: On OpenShift 4.18, administrators gain deeper insight into VM performance via new workload metrics. The monitoring stack can now show metrics for each VM’s allocated resources – including CPU usage, memory, network, and storage – similar to how it monitors container workloads. These metrics help with capacity planning and optimization. For instance, you can observe if a VM consistently underutilizes its CPU allocation and decide to downsize it, or identify VMs that need more resources. Having these performance metrics readily available in OpenShift’s dashboards enables data-driven tuning of virtualized workloads.

• Scaling and Multi-Cluster Visibility: In very large environments, OpenShift is also making strides. Red Hat has provided early previews of Grafana dashboards focused on virtualization at scale. One dashboard can analyze VM usage across clusters to recommend right-sizing of CPU or memory for VMs on different clusters (helping ensure performance while avoiding waste). While this is a preview, it signals a focus on performance optimization across multi-cluster deployments. Additionally, multi-cluster observability for OpenShift Virtualization continues to improve, so operators managing fleets of clusters can get a central view of their VM health and performance.

Expanded Guest OS and Security Support

• Windows Server 2025 Support: Many enterprises run Windows workloads, and OpenShift Virtualization 4.18 keeps pace with Microsoft’s latest. Red Hat validated OpenShift Virtualization on Windows Server 2025 on day one of Microsoft’s release. In fact, OpenShift 4.18 achieved Microsoft’s Server Virtualization Validation Program (SVVP) certification for Windows Server 2025. This guarantees that Windows VMs running on OpenShift meet Microsoft’s standards and are fully supported, reassuring customers that they can run new Windows Server instances on OpenShift as reliably as on a traditional hypervisor.

• vTPM Enhancements: Security features for VMs are bolstered by improvements to virtual Trusted Platform Modules (vTPMs). OpenShift already allowed adding a vTPM device to VMs (for uses like Windows BitLocker encryption); now in 4.18, this feature is more robust. Key enhancements include support for vTPM on block storage volumes and on standard (ReadWriteOnce) PVCs. Previously, vTPM might have required shared storage to persist data across node moves; with RWO (non-shared) support, even VMs that don’t live-migrate can use a vTPM. Moreover, OpenShift Virtualization now supports taking snapshots of VMs with a vTPM and restoring from those snapshots. (Cloning a vTPM-enabled VM or creating a new VM from such a snapshot is still not supported, since the TPM state can’t be duplicated for security reasons.) These enhancements let users confidently use vTPMs for encryption and secure boot scenarios on a wider range of VMs. For example, if you add a vTPM to a Windows VM, Windows will recognize it and allow BitLocker encryption to proceed even if the vTPM is not persistent across reboots. All of this helps enterprises meet compliance or security requirements for VM workloads on OpenShift.

AI Assistance and Automation

• OpenShift Lightspeed (AI Assistant) – in tech preview: OpenShift 4.18 introduces a highly useful way to help administrators and developers – a generative AI-powered chat assistant called OpenShift Lightspeed, integrated directly into the OpenShift web console. Think of it as an AI “copilot” for your cluster. Lightspeed has knowledge of OpenShift’s documentation and even specific OpenShift Virtualization runbook information. Users can ask it questions like “How do I attach a new disk to a VM?” or seek troubleshooting advice and get guided answers sourced from official docs.
  Impressively, when you open the chat assistant in the context of a specific VM, it becomes VM-aware – it can pull in that VM’s YAML configuration, logs, or events with one click to help diagnose issues. This integration can save a lot of time: instead of manually searching docs or copying logs, an admin can interact with the chatbot to quickly pinpoint configuration mistakes or get step-by-step guidance. While Lightspeed is an optional component (enabled via an operator), it showcases how AI can streamline cloud platform operations. For teams adopting OpenShift Virtualization, this means quicker onboarding (the AI can explain features) and faster resolution of problems, ultimately reducing downtime.

Ecosystem Integrations

• Backup and DR Integration: As enterprises run more VMs on OpenShift, backup and disaster recovery become critical. OpenShift 4.18 introduces policy-based backup and restore for VMs through integration with the OpenShift API for Data Protection (OADP) framework. In essence, you can now treat VMs similar to Kubernetes workloads when it comes to backup: define backup policies and use OADP (which ties into tools like Velero) to snapshot and restore not just Kubernetes resources but the VM disk data as well. This integration covers VMs and associated KubeVirt objects across clusters, which is important for multi-cloud or multi-cluster environments. It gives platform admins a consistent, automated way to protect VM workloads, whether the cluster is on-prem or in the cloud.

• Third-Party Ecosystem Support: Red Hat has been working with multiple partners to certify more tools on OpenShift Virtualization. A notable addition in 4.18 is Rubrik support. Rubrik (a popular data management and backup vendor) has validated its Security Cloud and backup platform to work with OpenShift Virtualization, meaning organizations can use Rubrik to back up and migrate OpenShift-hosted VMs alongside their other infrastructure. This kind of integration is a big win for enterprises, as it brings familiar backup/recovery workflows to OpenShift’s VM layer. Rubrik’s solution can take consistent snapshots of Kubernetes VM volumes, help in ransomware recovery (cyber-resilience), and offload VM data for long-term retention – all with the knowledge that it’s officially supported on OpenShift. Beyond backup vendors, Red Hat is also collaborating with systems integrators; for example, TEKsystems and AWS have partnered to help customers migrate existing virtualization workloads onto OpenShift on AWS, using OpenShift Virtualization as the target platform. These ecosystem expansions mean users have more choices and confidence when extending OpenShift’s virtualization capabilities – whether it’s protecting VMs, automating migrations, or integrating with cloud services.

Benefits for Users and Enterprises

Leveraging OpenShift from which to deploy and manage applications translates into real benefits for organizations adopting the platform:

• Unified Platform & Cost Savings: By enhancing OpenShift’s ability to handle both containers and virtual machines, Red Hat enables IT consolidation. Organizations can run legacy VMs and cloud-native apps side by side, simplifying operations and potentially reducing licensing costs. In fact, one Red Hat customer, Reist Telecom, reported a 50% decrease in VM licensing costs after moving to OpenShift for both virtualization and container-based workloads. Savings stem from avoiding expensive proprietary virtualization hypervisor costs and using a single platform for all workloads. A unified platform also means teams invest in one set of skills and tools, which improves efficiency.

• Faster Operations and Developer Productivity: The management improvements (UI enhancements, bulk actions, metrics, Lightspeed AI assistance) make platform administrators more productive. Routine tasks like rebooting multiple VMs or expanding a VM’s disk are quicker and don’t require special scripts or downtime. The AI integration can shorten troubleshooting time and onboarding for new administrators from hours to minutes by guiding admins through complex procedures or surfacing the right log snippet. For developers and testers, having self-service VM capabilities on OpenShift with easy networking and storage options means they can provision the environments they need faster, accelerating development cycles.

• Improved Network and Storage Flexibility: Features like UDN and live storage migration give enterprises much-needed flexibility in a cloud platform. For example, network engineers can apply familiar data center networking patterns (isolated L2 segments, BGP route sharing) to Kubernetes clusters – this eases integration with existing IT infrastructure and ensures multi-tenant security. Storage live migration enables infrastructure teams to perform maintenance or upgrades without scheduling lengthy downtime, as VMs can be moved off an old storage array live. The net effect is less disruption to business services and an easier time adopting new tech (like faster storage or new network topologies) under the hood.

• Enterprise Security & Compliance: OpenShift 4.18’s attention to security features benefits organizations running sensitive workloads. The GA Secrets CSI driver means apps can use secrets from external vaults such as HashiCorp Vault or AWS Secrets Manager with no plaintext secrets in etcd – a big plus for compliance. vTPM support improvements allow the use of disk encryption (BitLocker, etc.) and secure boot in VMs, helping meet compliance standards for protecting data at rest and in transit on VMs. And updated Windows support ensures companies can migrate to newer Windows Server versions without waiting, all under Red Hat’s support umbrella. These enhancements build confidence that OpenShift can handle mission-critical, regulated workloads.

• Ecosystem and Integration Benefits: The availability of the OpenShift Virtualization Engine edition provides a lower-cost on-ramp for virtualization use cases. Organizations that primarily want to modernize their VM infrastructure can start with this edition to enjoy OpenShift’s benefits (like consistent management and automation) for VMs only, then later transition to full OpenShift for containers and application modernization capabilities when ready. Meanwhile, integration with established enterprise tools – such as backup solutions (Rubrik, Vertas Net Backups) and storage from leading vendors such as NetApp, PortWorx, and Dell – means adopting OpenShift doesn’t require abandoning existing investments in tooling and infrastructure. Enterprises can extend their current processes (backup, DR, monitoring) to OpenShift VMs, which shortens the learning curve and improves reliability using proven solutions. All these integrations affirm that OpenShift is not an island, but rather an ever growing ecosystem supportive of hybrid cloud strategies.

Conclusion

Red Hat OpenShift 4.18 delivers a rich set of updates that reinforce its position as a leading hybrid cloud platform, especially for organizations looking to bring virtual machine workloads onto a modern application platform. This release’s general improvements – from networking flexibility with UDN/BGP to easier certificate and secret management – strengthen the core OpenShift platform for all users. But the standout is the focus on OpenShift Virtualization: 4.18 narrows the gap between traditional VM infrastructure and cloud-native infrastructure. Administrators get tools to manage VMs at scale (tree views, metrics, bulk actions) with the same ease as containers, and developers can more seamlessly work with VMs alongside containerized apps. Enhanced features like live storage migration and tenant networks show that OpenShift can handle complex enterprise VM scenarios (multi-tenant networking, zero-downtime storage ops). The result is greater agility and choice – teams can modernize at their own pace, running VMs and containers together and gradually refactoring apps without needing two completely separate environments. Backed by Red Hat’s official support and an expanding ecosystem of partners, OpenShift 4.18 provides a unified platform that can drive innovation while still caring for traditional workloads. Enterprises adopting these new features can expect improved efficiency, reduced costs, and a smoother path to hybrid cloud modernization.

For more information, check out the following links:

• Red Hat unveils OpenShift 4.18: Enhanced security and virtualization experience
• What’s New in OpenShift Virtualization 4.18
• OpenShift Virtualization Release Notes (4.18)