Merge pull request #88204 from jhradilek/CNV-42747-workload-updates

CNV-42747: Added a note about OCP 4.16

Author: stevsmit

modules/virt-about-control-plane-only-updates.adoc

@@ -12,6 +12,8 @@ After you update from the source EUS version to the next odd-numbered minor vers
 
 When the {product-title} update succeeds, the corresponding update for {VirtProductName} becomes available. You can now update {VirtProductName} to the target EUS version.
 
+For more information about EUS versions, see the link:https://access.redhat.com/support/policy/updates/openshift[Red Hat OpenShift Container Platform Life Cycle Policy].
+
 [id="preparing-to-update_{context}"]
 == Preparing to update
 

modules/virt-preventing-workload-updates-during-control-plane-only-update.adoc

@@ -8,6 +8,27 @@
 
 When you update from one Extended Update Support (EUS) version to the next, you must manually disable automatic workload updates to prevent {VirtProductName} from migrating or evicting workloads during the update process.
 
+[IMPORTANT]
+====
+In {product-title} 4.16, the underlying {op-system-first} upgraded to version 9.4 of {op-system-base-full}. To operate correctly, all `virt-launcher` pods in the cluster need to use the same version of {op-system-base}.
+
+After upgrading to {product-title} 4.16 from an earlier version, re-enable workload updates in {VirtProductName} to allow `virt-launcher` pods to update. Before upgrading to the next {product-title} version, verify that all VMIs use up-to-date workloads:
+
+[source,terminal]
+----
+$ oc get kv kubevirt-kubevirt-hyperconverged -o json -n openshift-cnv | jq .status.outdatedVirtualMachineInstanceWorkloads
+----
+
+If the previous command returns a value larger than `0`, list all VMIs with outdated `virt-launcher` pods and start live migration to update them to a new version:
+
+[source,terminal]
+----
+$ oc get vmi -l kubevirt.io/outdatedLauncherImage --all-namespaces
+----
+
+For the list of supported {product-title} releases and the {op-system-base} versions they use, see link:https://access.redhat.com/articles/6907891[{op-system-base} Versions Utilized by {op-system} and {product-title}].
+====
+
 .Prerequisites
 
 * You are running an EUS version of {product-title} and want to update to the next EUS version. You have not yet updated to the odd-numbered version in between.
@@ -206,4 +227,4 @@ $ oc get vmim -A
 
 .Next steps
 
-* You can now unpause the worker nodes' machine config pools.
+* Unpause the machine config pools for each compute node.