If you are using an ActiveMQ cluster, you benefit from reliable high performance and load balancing of messages. If ActiveMQ is down, the transaction will fail and any file(s) added to the Alfresco folder on your desktop will be deferred. In File Explorer/Finder, the file will show a blue icon and a notification is displayed on the system tray. When ActiveMQ is up and running again, the file is synced and shows a green icon in the File Explorer/Finder.