The default broker server

Hi all,
When I created a broker server in localhost by command-line,it shows that the broker server is create OK,but when I start the broker use command line ‘broker_start’,an issue occured ,the error is ‘Unable to open the connection to the host ‘localhost’.Error ‘java.net.connectException:Connection refused:connect’ was reported by the socket call.’
Is there anyone can help me to solve the problem? Or who can tell me how to create a broker server.Tks!