title: In docker,how to close the port expose by dockerfile?
body: <p>I've make a image by a dockerfile in which i expose a port by the line "expose 22".</p>
  
  <p>"sudo docker build -t mysql_server .  "</p>
  
  <p>after that,i find i didn't need the port.</p>
  
  <p>how can i do to close 22 port?</p>
  
  <p>EDIT:
  @Adrian Mouat @seanmcl</p>
  
  <p>The image is a mysql.So the data in database all in my container named "cliff_mysql56".if I rebuild the image and run it,I have to move all my data from this container to the new runner :(. That's the reason I don't want to rebuild.</p>