OCP allows users to change from any FeatureSet to CustomNoUpgrade and disallows users changing from CustomNoUpgrade to any other FeatureSet.

OCP also allows users to make changes to CustomNoUpgrade enabled and disabled lists.

MicroShift diverges from this pattern in that it does not allow FeatureGates/Sets to be changed after they are set. MicroShift does not allow changes to CustomNoUpgrade enabled/disabled lists.

    100%

1. Create config drop-in 

$ cat > /etc/microshift/config.d/features.yaml <<'EOF'
apiServer:
  featureGates:
    featureSet: "CustomNoUpgrade"
    customNoUpgrade: 
      enabled: ["FakeFeatureGate"]
EOF     

2. Restart MicroShift
3. Make a change to the custom featureGate list(s)

$ cat > /etc/microshift/config.d/features.yaml <<'EOF'
apiServer:
  featureGates:
    featureSet: "CustomNoUpgrade"
    customNoUpgrade: 
    enabled: ["FakeFeatureGate", "AnotherFakeFeatureGate"]
EOF          

    microshift fails to start on restart

    microshift should now fail to start if custom feature gates are changed