title: How to upgrade geoserver 2.18 bin.zip to geoserver 2.21 windows installer ( as a service)
body: <p>I am trying to upgrade geoserver from version 2.18.0 bin.zip  to version 2.21.1 (windows installer). If I understand correctly, then 2.18.0 uses a jetty server, and no jetty installation is required, this is provided by the geoserver.
  Version 2.18 uses a jetty server, and no jetty installation is required, this is provided by the geoserver. I installed 2.21.1 using the windows installer, first specifying the default address of the data folder. Everything seems to be installed, but the service starts and immediately turns off. How to overcome it? Do I need to install Tomcat first? Do I need to remove the jetty server, if so, how?  In the installation of the log - only 3 lines:</p>
  <blockquote>
  <p>ERROR : Nothing to start, exiting ...</p>
  <p>Usage: java -jar $JETTY_HOME/start.jar [options] [properties]
  [configs] java -jar $JETTY_HOME/start.jar --help # for more
  information
  Why is the jetty server listed in the log and not the tomcat?</p>
  </blockquote>