public List<String> getModifiableAttributes() {
    String[] modifiables = {HTTP_SERVICE_PORT, JMX_MANAGER_HTTP_PORT};
    return Arrays.asList(modifiables);
  }
child class can override this method to return a list of modifiable attributes no matter what
the default is

@return an empty list
geode-core/src/main/java/org/apache/geode/distributed/internal/AbstractDistributionConfig.java