Certain Types Of Udp Packets Are Blocked In Gl-Mt300n-V2 Version 4.3.18 And Are Not Blocked In Version 3.216

illimar · January 14, 2025, 8:03pm

I directed my OpenVpn server (10.8.0.1) to my application UDP ports 1162 and 1163 to the device at ip address 192.168.8.128. UDP port 1162 packets pass through fine on both versions, but UDP port 1163 packets are blocked on version

However, on version 3.216, UDP port 1163 packets get through. Below are screenshots of the device configuration and packet traffic. How can I understand what is causing the blocking of packets in version 4.3.18 and how can I avoid it?

bruce · January 15, 2025, 8:10am

Hello,

The MT300NV2 as the OpenVPN server with the port 1163 and protocol UDP.
It does not require to set up the port forwarding and open port on router in fact. The 1163 will be auto open for WAN when the OpenVPN server started.

VPN client test to verify if the 1163 UDP works, the port 1163 UDP can be connected, it is not blocked in v4.3.18:

illimar · January 15, 2025, 11:10am

Hi!
Thanks for answer ,but I don't use routers OPENVPN servers I Use windows OPENVPN server,see printscreens my system server side printscreen.

Client side mango version 4.3.18 missed packets from port 1163 server 10.8.0.1 to device 192.168.8.128
I downgrade mango to version 3.216 and evrithing working.
What I must do mango version 4.3.18 ?

Best regards,
Illimar

illimar · January 18, 2025, 6:29pm

I found a temporary solution to the problem. I turned off the encryption of my device's data exchange so that only visible ASCII characters remained in the data exchange and these packets were not blocked by Mango version 4.3.18. Could someone investigate why traffic on a port is blocked when there is a declaration of this port in the firewall?

hansome · January 23, 2025, 1:14am

I really can't think of anything special about port 1163,
Execute this command to check if port forward allows the connection to be established:

cat /proc/net/nf_conntrack|grep -e 1162 -e 1163 -e 1194