Firewall in LM 21.3 blocking UPnP from opening ports

[GloriousBread]

Firewall in LM 21.3 blocking UPnP from opening ports, when firewall is disabled everything works, when firewall is enabled UPnP cannot open ports on router for connections outside my local network.

On Windows it works fine out of the box, Linux doesn’t create firewall rules for connections. What are the required firewall rules, I can add myself if NoMachine cannot do it itself.

[Irek]

It seems like your firewall might be blocking UPnP traffic from your router, which could prevent the router’s response to the UPnP request from reaching your machine.

If you’re using the default firewall on Linux Mint, which is typically ‘ufw’, you can allow incoming UPnP traffic from your router by executing the following command:

ufw allow from 192.168.1.1 port 1900 to any proto udp

After allowing this traffic, you can initiate UPnP mapping by running:

/etc/NX/nxserver --upnpmap

Once done, UPnP should be operational on your machine. Remember to repeat this process on every machine where UPnP functionality is required.

Note: To find your router’s IP address, you can use the following command:

ip route | grep default

If you’re using any additional outer firewalls, ensure to add a similar firewall rule to allow UPnP traffic as mentioned above.

[Author]

Posts