When I use our standard deployment configuration (which we've successfuly used from 4.x till latest 5.3.x), the cache module startup for the public instance crashes with net.sf.ehcache.CacheException: javax.management.InstanceAlreadyExistsException: net.sf.ehcache:type=CacheManager,name=#info.magnolia.module.cache.ehcache.EhCacheFactory#cacheManager

The deployment configuration is that the instances are deployed to webapps/magnoliaAuthor/ROOT and webapps/magnoliaPublic/ROOT, and we have two separate Service definitions in the Tomcat's server.xml, with appBase pointing to webapps/magnoliaAuthor and webapps/magnoliaPublic, respectively.

Btw. the cache is actually working, but the flushing commands are not.

The cause (and solution) could be probably similar to these in the old MAGNOLIA-786