I did an upgrade on my local Workbench from 5.x to 8.0.23. Since the upgrade unfortunately I can connect to my local MySql database Version 5.7.20 and also to a remote database with version 8.0.15, but I can't connect to a remote database with version 5.6.20. With the old Workbench the connection was fine.
Because I can connect to the remote database 8.0.15, I think, that all issues about network and firewall are ok.
So, what is the raison that I can't connect to the remote database version 5.6.20?