This is a clone of issue OCPBUGS-66964. The following is the description of the original issue:

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(Feel free to update this bug's summary to be more specific.)
Component Readiness has found a potential regression in the following test:

[sig-mco][OCPFeatureGate:MachineConfigNodes] [Serial]Should have MCN properties matching associated node properties for nodes in custom MCPs [apigroup:machineconfiguration.openshift.io] [Suite:openshift/conformance/serial]

Extreme regression detected.
Fishers Exact probability of a regression: 100.00%.
Test pass rate dropped from 100.00% to 74.07%.

Sample (being evaluated) Release: 4.21
Start Time: 2025-12-01T00:00:00Z
End Time: 2025-12-08T12:00:00Z
Success Rate: 74.07%
Successes: 20
Failures: 7
Flakes: 0
Base (historical) Release: 4.20
Start Time: 2025-09-21T00:00:00Z
End Time: 2025-10-21T23:59:59Z
Success Rate: 100.00%
Successes: 84
Failures: 0
Flakes: 0

View the test details report for additional context.

This is an azure report, but seeing several other hits for this test on multiple platforms as well as :

[sig-mco][OCPFeatureGate:MachineConfigNodes] [Serial]Should properly transition through MCN conditions on rebootless node update [apigroup:machineconfiguration.openshift.io] [Suite:openshift/conformance/serial]

Follow the triage report link in the comment that will appear on this bug once filed for links to all reported regressions for these.

These jobs seem to be failing ONLY on MachineConfigNodes tests, and thus the likelihood of an actual feature regression seems high here.

Filed by: dgoodwin@redhat.com