private static Integer createServerCache() throws Exception {
    new RedundancyLevelTestBase().createCache(new Properties());
    AttributesFactory<String, String> factory = new AttributesFactory<>();
    factory.setScope(Scope.DISTRIBUTED_ACK);
    factory.setEnableSubscriptionConflation(true);
    factory.setDataPolicy(DataPolicy.REPLICATE);
    RegionAttributes<String, String> attrs = factory.createRegionAttributes();
    cache.createVMRegion(REGION_NAME, attrs);

    CacheServer server1 = cache.addCacheServer();

    int port = getRandomAvailableTCPPort();
    server1.setMaximumTimeBetweenPings(180000);
    server1.setPort(port);
    server1.start();
    return server1.getPort();
  }
@param connectedServers is the expected number of connected servers (1 or more)
@param redundantServers is the expected number of redundant servers (0 or more)
geode-core/src/distributedTest/java/org/apache/geode/internal/cache/tier/sockets/RedundancyLevelTestBase.java