title: Problem with isReachable in InetAddress class
body: <p>As an assignment I have to find all the alive computers on a LAN.  For which I am using <code>isReachable</code> function of <code>InetAddress</code> class.  But problem is that nothing is shown reachable to me. So I tried to have <code>isReachable</code> with Google's IP but still this is unreachable.</p>
  
  <p>Here is the code:</p>
  
  <pre><code>import java.net.*;
  
  public class alive{
      public static void main(String args[]){
          try{
              InetAddress ia = InetAddress.getByAddress(new byte[]{(byte)209, (byte)85, (byte)153, (byte)104});
              boolean b = ia.isReachable(10000);
              if(b){
                  System.out.println("Reachable");
              }
              else{
                  System.out.println("Unrachable");
              }
  
          }catch(Exception e){
              System.out.println("Exception: " + e.getMessage());
          }
      }
  }
  </code></pre>
  
  <p>Output is : <code>Unreachable</code></p>