title: Selenium Node failed to register with the hub
body: <p>I ran the command below on machine as a hub(IP Addr:192.168.55.209, OS:Ubuntu):</p>
  
  <pre><code>java -jar selenium-server-standalone-2.25.0.jar \ -role hub -port 4444
  </code></pre>
  
  <p>Then I ran another command below on another machine as a node(OS: Windows 7 64bit):</p>
  
  <pre><code>java -jar "selenium-server-standalone-2.25.0.jar" \ -role node -port 5555 -hub http://192.168.55.209:4444/grid/register \browser browserName=firefox,platform=WINDOWS
  </code></pre>
  
  <p>But I got error message below: Please help find what's the problem. (I've disabled the firewall)</p>
  
  <pre><code>&gt; Nov 05, 2012 5:12:37 PM org.openqa.grid.selenium.GridLauncher main
  &gt; INFO: Launching a selenium grid node Nov 05, 2012 5:12:38 PM
  &gt; org.openqa.grid.internal.utils.SelfRegisteringRemote startRemoteServer
  &gt; WARNING: error getting the parameters from the hub. The node may end
  &gt; up with wrong timeouts.A JSONObject text must begin  with '{' at
  &gt; character 1 17:12:38.064 INFO - Java: Oracle Corporation 23.3-b01
  &gt; 17:12:38.066 INFO - OS: Windows 7 6.1 amd64 17:12:38.068 INFO -
  &gt; v2.25.0, with Core v2.25.0. Built from revision 17482 17:12:38.172
  &gt; INFO - RemoteWebDriver instances should connect to:
  &gt; http://127.0.0.1:5555/wd/hub 17:12:38.174 INFO - Version Jetty/5.1.x
  &gt; 17:12:38.174 INFO - Started
  &gt; HttpContext[/selenium-server/driver,/selenium-server/driver]
  &gt; 17:12:38.175 INFO - Started
  &gt; HttpContext[/selenium-server,/selenium-server] 17:12:38.175 INFO -
  &gt; Started HttpContext[/,/] 17:12:38.177 INFO - Started
  &gt; org.openqa.jetty.jetty.servlet.ServletHandler@508969c3 17:12:38.177
  &gt; INFO - Started HttpContext[/wd,/wd] 17:12:38.181 INFO - Started
  &gt; SocketListener on 0.0.0.0:5555 17:12:38.181 INFO - Started
  &gt; org.openqa.jetty.jetty.Server@19dda5ce 17:12:38.183 INFO - using the
  &gt; json request :
  &gt; {"class":"org.openqa.grid.common.RegistrationRequest","capabilities":[{"pla
  &gt; tform":"VISTA","seleniumProtocol":"Selenium","browserName":"*firefox","maxInstances":5},{"platform":"VISTA","seleniumPro
  &gt; tocol":"Selenium","browserName":"*googlechrome","maxInstances":5},{"platform":"VISTA","seleniumProtocol":"Selenium","bro
  &gt; wserName":"*iexplore","maxInstances":1},{"platform":"VISTA","seleniumProtocol":"WebDriver","browserName":"firefox","maxI
  &gt; nstances":5},{"platform":"VISTA","seleniumProtocol":"WebDriver","browserName":"chrome","maxInstances":5},{"platform":"WI
  &gt; NDOWS","seleniumProtocol":"WebDriver","browserName":"internet
  &gt; explorer","maxInstances":1}],"configuration":{"port":5555,
  &gt; "register":true,"host":"192.168.55.94","proxy":"org.openqa.grid.selenium.proxy.DefaultRemoteProxy","maxSession":5,"hubHo
  &gt; st":"192.168.55.209","role":"node","registerCycle":5000,"hub":"http://192.168.55.209:4444/grid/register","hubPort":4444,
  &gt; "url":"http://192.168.55.94:5555","remoteHost":"http://192.168.55.94:5555"}}
  &gt; 17:12:38.185 INFO - starting auto register thread. Will try to
  &gt; register every 5000 ms. 17:12:38.185 INFO - Registering the node to
  &gt; hub :http://192.168.55.209:4444/grid/register 17:12:38.189 INFO -
  &gt; couldn't register this node : Error sending the registration request.
  &gt; 17:12:43.194 INFO - couldn't register this node : hub down or not
  &gt; responding. 17:12:48.197 INFO - couldn't register this node : hub down
  &gt; or not responding.
  </code></pre>