I have a standalone server running Home Assistant with a feature that allows me to https://www.home-assistant.io/integrations/emulated_roku/" target="_blank"> emulates a Roku appliance for my Harmony Hub to discover and include in its activities for running customized scripts.
My UPNP discovery needs seem to be covered (Thanks to Nick and MiniUPNP) when I run my server without a firewall. Since this server is running in the HotLan. I would prefer to enable the firewall but I have had some difficulties figuring out what ports below are needed to allow the Harmony Hub to reach the emulated Roku device

I tried to allow in UDP port 1900 but was not successful at penetrating the firewall. Any suggestions to what ports are needed for the discovery to work.and reduce the security vulnerabilities.