Thanks fukawi2 Do you have any idea how to setup this configuration. It was not possible by using the gui. I haven't found settings on the GUI, which enables me to configure a Nas2Nas synchronization. (Two days later: ) Now I spent one more time 4 hours to find out how to synchronize mine two NAS devices. For me is important to synchronize one folder. It doesn't matter if it is read only or not. That would be nice, but not a main goal. If anybody have an advice it would be great. I searched for a client version for a synology NAS operating system, but I haven’t found an answer. Cheers