title: Embedded Tomcat 7 cluster using spring-boot
body: <p>I developing web-application using spring-boot.
  And I want to cluster spring-boot embedded tomcat 7.
  I searched all day long, but answers are almost using server.xml and apache.
  But the way of using server.xml on spring-boot, I couldn't find it.
  I think I need usage of configuration multiple connector, and engine, and so on.
  I don't know, it is right way.
  Please show me the way.</p>