code: public static InetAddress getInetAddress(String hostName) {
          try {
              return InetAddress.getByName(hostName);
          } catch (UnknownHostException e) {
              throw new IllegalStateException("Unknown host: " + e.getMessage() +
                      ". Make sure you have specified the 'GelfUDPAppender.remoteHost' property correctly in your logback.xml'");
          }
      }
docs: Gets the Inet address for the GelfUDPAppender.remoteHost and gives a specialised error message if an exception is thrown
  
  @return The Inet address for GelfUDPAppender.remoteHost