The stun service is deployed using Docker, which means that the talk container’s IP address is always the LAN IP address, but the published IP address is always the LAN IP address. This makes stun almost impossible to work because it always tries to connect to a Docker internal address.
like this:
Shouldn’t this situation be very common? Is there any good way to solve this problem? Although falling back to turn can still be used, it is not the best way.
Hello @ruins,
welcome to the community of Nextcloud 
You started a topic in support category. Unfortunately you ignored the template and a lot of information to help you is missing. Please edit your original post and add all required details like Nextcloud version, webserver type and version, os version, related log file content. Use the support template.
Without additional information the community members cannot help you. Please use search we have many stun and turn topics showing config and troubleshooting steps.
Regards,
wwe