@Test
    void implicitly_downed_group_nodes_are_annotated_with_group_reason() {
        final ClusterFixture fixture = ClusterFixture
                .forHierarchicCluster(DistributionBuilder.withGroups(2).eachWithNodeCount(2))
                .bringEntireClusterUp()
                .reportStorageNodeState(3, State.DOWN);
        final ClusterStateGenerator.Params params = fixture.generatorParams().minNodeRatioPerGroup(0.51);

        final AnnotatedClusterState state = ClusterStateGenerator.generatedStateFrom(params);
        assertThat(state.getNodeStateReasons(),
                hasStateReasonForNode(storageNode(2), NodeStateReason.GROUP_IS_DOWN));
    }
Maintenance mode overrides all reported states, even Down.
clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/ClusterStateGeneratorTest.java