Chia Docker (on Synology NAS) Full Node - Question about connecting remote harvesters

[Jazzman303]

This question is about how to establich a working connection between remote harvesters and a full-node Docker Installation running on a Synology NAS.

My setup: Full Node running on a Synology DS1621xs+ currently joined in a pool. Second machine: Mac running just the harvester. Third machine (for testing, interim): Windows 10 PC running another full node. 300 TB of pool plots.

The currenct problem is, that the Mac harvester cannot be connected to the Synology Full Node (Docker). Error in the debug.log is:
INFO Reconnecting to peer {'host': '192.xxx.xxx.xx', 'port': 8447}
DEBUG Connecting: wss://192.xxx.xxx.xx:8447/ws, Peer info: {'host': '192.xxx.xxx.xx', 'port': 8447}
INFO Cannot connect to host 192.xxx.xxx.xx:8447 ssl:<ssl.SSLContext object at 0x10e54d440> [Connect call failed ('192.xxx.xxx.xx', 8447)]

When i change the farmer_peer to use the Windows 10 PC Full Node and restart the harvester instead, the Windows 10 PC instantly sees the Mac harvester and the Mac harvester´s problems in the debug.log are gone.

Ports 8447 and 8448 on the docker image are open and passed so it .. should(?) .. understand that a farmer_peer setting to Synology_IP Port 8447 means the docker image. But this is where i´m not sure. I know that the docker is a virtual thing, so it has an own IP (hostnmae -i shows that its at 127.xxx.xxx.xxx "inside" the docker)

I had the setup running in the other direction before, the synology being a pure harvester contributing to the windows 10 PC full node. That worked well without fiddling in network settings and special port entries in the firewalls.

I´m glad for any help and insight.