<table align="center">
    <thead>
      <tr>
        <th th:text="host">host</th>
        <th th:text="status">status</th>
        <th th:text="command">command</th>
      </tr>
    </thead>
    <tbody>
      <tr th:each="hostInstance: ${allHosts}">
        <td th:text="${hostInstance.name}"></td>
        <td th:text="${hostInstance.status}"></td>
        <td>
        <button type="submit" name="start" th:value="${hostInstance.name}" th:text="Start"></button>
        </td>
      </tr>
    </tbody>
  </table>

@RequestMapping(value="/network", params={"start"})
public String startApp(final NetworkCluster networkCluster, final BindingResult bindingResult, final HttpServletRequest req, Model model) {
    String result = req.getParameter("start");
    System.out.println(result + " is clicked");
    return "redirect:/network";
}

<table align="center">
    <thead>
      <tr>
        <th>host</th>
        <th>status</th>
        <th>command</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td>machine_1</td>
        <td>down</td>
        <td>
        <div>
        <p><button type="submit" name="start" value="machine_1">Start</button></p>

        </div>
        </td>
      </tr>
      <tr>
        <td>machine_2</td>
        <td>down</td>
        <td>
        <div>
        <p><button type="submit" name="start" value="machine_2">Start</button></p>

        </div>
        </td>
      </tr>

    </tbody>
  </table>