private List<Group> getGroupsWithIndexes(Collection<Integer> groupIndexes) {
        return clusterInfo.getStorageNodeInfos().stream()
                          .map(NodeInfo::getGroup)
                          .filter(group -> groupIndexes.contains(group.getIndex()))
                          .collect(Collectors.toList());
    }
Returns a disallow-result, if there is a node in the group with wanted state != UP.
clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/NodeStateChangeChecker.java