Properties getLocatorProperties(String locatorsString, boolean enableCC) {
    Properties props = new Properties();
    props.setProperty(DistributionConfig.MCAST_PORT_NAME, "0");
    props.setProperty(DistributionConfig.LOCATORS_NAME, locatorsString);
    props.setProperty(DistributionConfig.LOG_LEVEL_NAME, DUnitLauncher.logLevel);
    props.setProperty(DistributionConfig.ENABLE_CLUSTER_CONFIGURATION_NAME, enableCC + "");
    // do not start http service to avoid port conflict between upgrade tests
    props.setProperty(DistributionConfig.HTTP_SERVICE_PORT_NAME, "0");
    return props;
  }
This test starts up multiple servers from the current code base and multiple servers from the
old version and executes puts and gets on a new server and old server and verifies that the
results are present. Note that the puts have overlapping region keys just to test new puts and
replaces
geode-core/src/upgradeTest/java/org/apache/geode/internal/cache/rollingupgrade/RollingUpgrade2DUnitTestBase.java