@Override
  public int getSSLPort() {
    if (hasSSLPort()) {
      return ports.get(PortType.SSL).getPort();
    } else {
      throw new IllegalStateException("No SSL port exists for the Data Node " + hostname + ":" + portNum);
    }
  }
Gets the DataNode's SSL port number.

@return Port number upon which to establish an SSL encrypted connection with the DataNodeId.
@throws IllegalStateException Thrown if no SSL port exists.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/DataNode.java