First, the existing web application has to be removed. For the period of the update a downtime must be scheduled because the web application is temporarily not available. The deployment package ('atlasfx.war' file) of the existing system must be saved at all cost, so that the old 'atlasfx.war' file can be restored in case of problems. For this purpose it is recommended to create a directory 'undeploy' in the catalina base folder. The old deployment package can be put here.