Monitor Argon WiFi traffic using Wireshark or similar

General
1

I am trying to monitor the traffic between my Argon and my Raspberry pi to see what type of traffic is going across my network. I am using a laptop running Wireshark V 3.0.4. The laptop is connected to the same wireless router as my Argon.
It is successfully posting data to my Pi, and everything is working fine, the argon does talk to the pi and vice versa, except that I don’t see any of the traffic between the PI and the Argon with wireshark…
The Argon is sending data to the Pi by going to a PHP webpage url on the pi. the code snippit is below
I am a Wireshark newbie, so I am sure I am missing something here.

// https://community.particle.io/t/simple-post-request-to-a-server/23707
TCPClient client;                          
const char serverHost[] = "192.168.1.100";  // The server the data is being sent to
const int serverPort = 80;

Then later.................. 
			client.println("POST /DBWriteParam.php?" + command +" HTTP/1.1");
			client.println("Host: 192.168.1.100");
			client.printlnf("Content-Length: %d", command.length());
			client.println("Content-Type: text/plain");
			client.println();
			client.println(command);
			client.flush();
2

Hi John!

Wireshark allows you to spy traffic in the local interfaces of your laptop and mostly for traffic that goes through the laptop. Unless you have a very upscale router that sends all traffic it receives to a port and you are spying in that port (if you have a home router, it may not have this feature, which I do not know the name), I’ll say you won’t see any traffic from Argon to Pi in your laptop.

If you want to see the traffic between the pi and your Argon you’ll need to run wireshark, or tcpdump (the linux utility) on the pi itself. There you’ll see everything the pi sends and receives.

Cheers,
Gustavo.

3

I didn’t think about it only watching the traffic going through the router along the laptops interface. I was remembering the old days with broadcasting hubs, and I guess I was thinking WiFi would act more like the hub rather than the specific port.

Thanks for clearing that up.

John

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