docs: @Override
      public Map<ServerGroup, EVCacheServerGroupConfig> discoverInstances(String appName) throws IOException {
          final String propertyName = appName + "-NODES";
          final String nodeListString = EVCacheConfig.getInstance().getDynamicStringProperty(propertyName, "").get();
          if (log.isDebugEnabled()) log.debug("List of Nodes = " + nodeListString);
          if(nodeListString != null && nodeListString.length() > 0) return bootstrapFromSystemProperty(nodeListString);
          
          if(env != null && region != null) return bootstrapFromEureka(appName);
          
          return Collections.<ServerGroup, EVCacheServerGroupConfig> emptyMap();
      }