VSHN Managed OpenShift: Upgrade to OpenShift version 4.15

As we start to prepare to rollout upgrades to OpenShift v4.15 across all our customers clusters it is a good opportunity to look again at what was in the Red Hat OpenShift 4.15 release. It brought Kubernetes 1.28 and CRI-O 1.28 and it was largely focused on small improvements in the core platform and enhancements to how OpenShift runs on underlying infrastructure including bare-metal and public cloud providers.

The Red Hat infographic highlights some of the key changes:

For our VSHN Managed OpenShift and APPUiO customers, we want to highlight the key changes in the release that are relevant for them.

Across all VSHN Managed OpenShift clusters – including APPUiO

Our summary highlights that apply are the following:

• OpenShift 4.15 is based on Kubernetes 1.28 and CRI-O 1.28
• Update to CoreDNS 1.11.1
• There are some node enhancements (such faster builds for unprivileged pods, and compatibility of multiple image repository mirroring objects)
• The release also brings updated versions for the monitoring stack (Alertmanager to 0.26.0, kube-state-metrics to 2.10.1, node-exporter to 1.7.0, Prometheus to 2.48.0, Prometheus Adapter to 0.11.2, Prometheus Operator to 0.70.0, Thanos Querier to 0.32.5)
• It also includes some additional improvements and fixes to the monitoring stack
• There are some changes to the Bare-Metal Operator so that it now automatically powers off any host that is removed from the cluster
• There are some platform fixes including some security related ones like securing the cluster metrics port using TLS
• OLM (Operator Lifecycle Management is being introduced as v1 and this brings three new life cycle classifications for cluster operators that are being introduced: Platform Aligned, for operators whose maintenance streams align with the OpenShift version; Platform Agnostic, for operators who make use of maintenance streams, but they don’t need to align with the OpenShift version; and Rolling Stream, for operators which use a single stream of rolling updates.

On VSHN Managed OpenShift clusters with optional features enabled

The changes that might relate to some VSHN Managed OpenShift customers who have optional features enabled would include:

• OpenShift Service Mesh 2.5 based on Istio 1.18 and Kiali 1.73
• Enhancements to RHOS Pipelines
• Machine API – Defining a VMware vSphere failure domain for a control plane machine set (Technology Preview)
• Updates to hosted control planes within OSCP
• Bare-Metal hardware provisioning fixes

Changes not relevant to VSHN customers

There are a number of network related changes in this release, but these are not relevant for VSHN managed clusters as these are mostly running Cilium. It is also interesting to note the deprecation of the OpenShift SDN network plugin, which means no new clusters can leverage that setup. Additionally, there are new features related to specific cloud providers (like Oracle Cloud Infrastructure) or specific hardware stacks (like IBM Z or IBM Power).

The changes to handling storage and in particular storage appliances is also not relevant for VSHN customers as none of the storage features affect how we handle our storage on cloud providers or on-prem.

Features in OpenShift open to customer PoCs before we enable for all VSHN customers

We do have an interesting customer PoC with Red Hat OpenShift Virtualization which is an interesting feature that continues to mature in OpenShift 4.15. We are excited to see the outcome of this PoC and to potentially making that available to all our customers looking to leverage VMs inside OpenShift. We know due to the pricing changes from Broadcom that this is an area many companies and organizations are looking at. Moving from OpenShift running on vSphere to running on bare metal and having VMs inside OpenShift is an exciting transformation, and we hope to be able to bring an update on this in an upcoming separate blog post.

Likewise, we are open to customers who would like to explore leveraging OpenShift Serverless (now based on Knative 1.11 in Openshift 4.15) or perhaps with the new OpenShift Distributed Tracing Platform that is now at version 3.2.1 in the OpenShift 4.15 release (this version includes both the new platform based on Tempo and the now deprecated version based on Jaeger). This can also be used together with the Red Hat Open Telemetry Collector in OpenShift 4.15. There are also new versions of OpenShift Developer Hub (based on Backspace), OpenShift Dev Spaces and OpenShift Local. These are all interesting tools, part of the Red Hat OpenShift Container Platform.

If any of the various platform features are interesting for any existing or new VSHN customers, we would encourage you to reach out so we can discuss potentially doing a PoC together.

Summary

Overall, OpenShift 4.15 brings lots of small improvements but no major groundbreaking features from the perspective of the clusters run by VSHN customers. For those interested in the nitty gritty details of the OpenShift 4.15 release, we refer you to the detailed Red Hat release notes, which go through everything in detail.

VSHN customers will soon be notified about the upgrades to their specific clusters.

Interested in VSHN Managed OpenShift?

Head over to our product page VSHN Managed OpenShift to learn more about how VSHN can help you operate your own OpenShift cluster including setup, 24/7 operation, monitoring, backup and maintenance. Hosted in a public cloud of your choice or on-premises in your own data center.