Why port forwarding feature is not working on my router?

Please follow the steps below to troubleshoot port forwarding failures on the MERCUSYS routers.

Step 1: Ensure the server is accessible from the internal network.

Please double-check the IP address and the port number of the server. Check if you can access that server from the local network.

If you are unable to access the server in your local network, please check the settings of your server.

Step 2: Check the port forwarding settings in the router.

Ensure you configure the correct external and internal ports for the appropriate device.

Step 3: Check the firewall setting.

Windows firewall will block the connection from the different subnet, and it will divide the difference according to the network location you have chosen.

Please disable the firewall or set your network to Private/Home network on the Winodws device.

Step 4: Pay attention to the router’s WAN IP address in the status page.

If there are still problems, please check the WAN IP address on the status page of the router, and verify it’s a public IP address.

For MERCUSYS Wi-Fi Router, you can log in to the web management page and go to Advanced > Network > Status to check the WAN IP.

Note:

The WAN IP is assigned dynamically by the internet service provider (ISP). If the WAN IP address of the router is not a public IP address, but a private IP address, that means there is another NAT device connected to the WAN port of the router. You need to open the service ports on that device as well.

For most of the 4G/5G router, the ISP usually gives the private IP Address. If you want to use port forwarding, please contact your ISP to request a public IP address or do the port forwarding in their part.

Private IPv4 addresses have the following class configurations.

Class A IP addresses: 10.0.0.0 - 10.255.255.255

Class B IP addresses: 172.16.0.0 - 172.31.255.255

Class C IP addresses: 192.168.0.0 - 192.168.255.255

Carrier Grade NAT (CGNAT) addresses: 100.64.0.0 - 100.127.255.255

Step 5: Check the IP setting on the client.

The client’s IP should be the same subnet as the router, and the gateway on the client’s setting should be the router’s LAN IP address. Some devices need to set static IP on the Internet setting. Or you can configure an IP address reservation for the client.

If you still have the issue with port forwarding, Please contact MERCUSYS Technical Support with the result of the above troubleshooting steps.