HL7618RD and Linux. Outbound TCP connections work fine. All incoming ports blocked. Even Ping!

Hello Everyone,
I am using HL7618RD on an embedded Linux board (Debian 9 Linux) and have successfully connected to Internet using CDC/NCM on USB. My data plan gives me a static IP and I can connect to any website without any issue.
My issue is with the incoming traffic. If I ping my board using the public static IP, I get no reply. Same goes for the web server running on the Linux board or the SSH server running.

It is as if all ports in the HL7618RD are blocked.

There is no firewall running on the Linux system. By the way, if I connect via the Ethernet port, then I can ping and SSH into the board.

I can’t seem to find any documentation on unblocking the ports in the module.

Any help you guys can provide is much appreciated.


Hi @owais.kidwai

Which firmware are you using? If you are not in the latest firmware, please download the latest one and retry.

Please follow the attached documents Data call using NCM interface.docx (694.6 KB)

You can get the firmware here AirPrime HL7618RD VZW Firmware V1.10

Please help to tick “Solutions” if your question is answered.

Hi Donald.
Thanks for your reply.
I am using v1.1 which I updated via FOTA.
I had followed a similar document to connect my Linux board to Internet. That works fine. I can access websites and browse without any issue.
What I wan is to SSH into my board and it may not be a HL7618 issue. I am afraid that the static IP assigned to me is not a public static IP but rather a private static IP in Kore wireless network.
I have asked them and waiting for a reply. I am a newbie when it comes to putting a cellular module on an embedded Linux board. Maybe the right way to access my field device is to keep using a private static IP and VPN into Kore’s network and then SSH into the device. Anyway, once I hear from them I will update this thread.


Hi Donald.
As I suspected it was the IP issued by the carrier. The IP was not public static IP. Once With proper IP I get the connection and I can access the unit remotely using SSH.