private int extractSeqNum(String nodeName) {
    // Extract the sequence number of this ephemeral-sequential znode.
    String ephSeqVersionStr = nodeName.substring(workerNodePrefix.length());
    try {
      return Integer.parseInt(ephSeqVersionStr);
    } catch (NumberFormatException e) {
      LOG.error("Cannot parse " + ephSeqVersionStr + " from " + nodeName, e);
      throw e;
    }
  }
Get the ensemble server addresses from the configuration. The format is: host1:port,
host2:port..

@param conf configuration
llap-client/src/java/org/apache/hadoop/hive/registry/impl/ZkRegistryBase.java