OSDOCS-14370: Documented the 4.17.26 z-stream release notes

Author: dfitzmau

release_notes/ocp-4-17-release-notes.adoc

@@ -2879,6 +2879,49 @@ This section will continue to be updated over time to provide notes on enhanceme
 For any {product-title} release, always review the instructions on xref:../updating/updating_a_cluster/updating-cluster-web-console.adoc#updating-cluster-web-console[updating your cluster] properly.
 ====
 
+// 4.17.26
+[id="ocp-4-17-26_{context}"]
+=== RHSA-2025:4012 - {product-title} {product-version}.26 bug fix and security update advisory
+
+Issued: 23 April 2025
+
+{product-title} release {product-version}.26 is now available. The list of bug fixes that are included in the update is documented in the link:https://access.redhat.com/errata/RHSA-2025:4012[RHSA-2025:4012] advisory. The RPM packages that are included in the update are provided by the link:https://access.redhat.com/errata/RHBA-2025:4014[RHBA-2025:4014] advisory.
+
+Space precluded documenting all of the container images for this release in the advisory.
+
+You can view the container images in this release by running the following command:
+
+[source,terminal]
+----
+$ oc adm release info 4.17.26 --pullspecs
+----
+
+[id="ocp-4-17-26-known-issues_{context}"]
+==== Known issues
+
+* There is a known issue when the grandmaster clock (T-GM) transitions to the Locked state too soon. This happens before the Digital Phase-Locked Loop (DPLL) completes its transition to the `Locked-HO-Acquired` state, and after the Global Navigation Satellite Systems (GNSS) time source is restored.
+(link:https://issues.redhat.com/browse/OCPBUGS-54534[*OCPBUGS-54534*]) 
+
+
+[id="ocp-4-17-26-bug-fixes_{context}"]
+==== Bug fixes
+
+// SME review
+* Previously, the Single Root I/O Virtualization (SR-IOV) virtual function (VF) changed the maximum transmission unit (MTU) to an unexpected value when a pod was deleted. With this release, the SR-IOV Container Network Interface (CNI) now reverts any unexpected MTU value changes to the original value so that this issue no longer exists. (link:https://issues.redhat.com/browse/OCPBUGS-54392[*OCPBUGS-54392*])
+
+// SME review
+* Previously, when you attempted to create a validating webhook for a resource that is managed by the `oauth` API server, the validating webhook was not created. This issue occurred because of a communication issue with the `oauth` API server and the data plane. With this release, a Konnectivity proxy sidecar has been added to bridge communications between the `oauth` API server and the data plane so that you can now create a validating webhook for any resource that the `oauth` API server manages.  (link:https://issues.redhat.com/browse/OCPBUGS-54841[*OCPBUGS-54841*])
+
+// https://issues.redhat.com/browse/OCPBUGS-54750 a CVE? 
+
+* Previously, virtual machines (VMs) in a cluster that ran on {azure-first} failed because the attached network interface controller (NIC) was in a `ProvisioningFailed` state. With this release, the Machine API controller now checks the provisioning status of a NIC and refreshes the VMs on a regular basis to prevent this issue. (link:https://issues.redhat.com/browse/OCPBUGS-54393[*OCPBUGS-54393*]) 
+
+
+
+[id="ocp-4-17-26-updating_{context}"]
+==== Updating
+To update an {product-title} 4.17 cluster to this latest release, see xref:../updating/updating_a_cluster/updating-cluster-cli.adoc#updating-cluster-cli[Updating a cluster using the CLI].
+
 // 4.17.25
 [id="ocp-4-17-25_{context}"]
 === RHSA-2025:3798 - {product-title} {product-version}.25 bug fix and security update advisory