Choosing a local address

Many hosts have more than one IP address. This is especially common at web server farms where a single machine is shared by multiple sites. By default, a server socket binds to all available IP addresses. That is it accepts connections addressed to any of the local IP addresses on a given port. However you can modify that behavior with this constructor:

 public ServerSocket(int port, int backlog, InetAddress bindAddr) 
  throws IOException

You must also specify the queue length in this constructor.

  try {
    InetAddress ia = InetAddress.getByName("199.1.32.90");
    ServerSocket ss = new ServerSocket(80, 50, ia);
  }
  catch (IOException e) {
    System.err.println(e);
  }

How would you bind to some but not all IP addresses on the server?

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Last Modified April 18, 1997
Copyright 1997 Elliotte Rusty Harold
elharo@metalab.unc.edu