Firware OS5 and Rsync

My Cloud OS 5 Personal & Network Attached Storage My Cloud EX Series
1

Would like to see a solution for backing up using to RSYNC from another platform e.g. QNAP or similar WD platform e.g. with different firmware versions to the WDEX2Ultra fimware 5.0.6.115 or higher. At the moment I cannot use the root password from the WDEXUltra when I want to establish an Rsync connection. But I also cannot make a remote backup between two WDEX2Utra’s with firmware version 2.40.175 and 5.06.115 on the same LAN. As long as there is no solution For Rsync, I cannot upgrade my WDEX2Ultra to firmware 5.0.6.115. Can access the WDEX2Utra’s via SSH but with Firmware 5.0.6.115 I can’t find a rsync.pid file in / var / run / Something is blocking the creation of the file or it
is in a different location? Has anyone more information about Rsync or WD’s remote backup?