Hello,
I have OpenWrt 24.10.1 on Cudy TR1200 v1 (arch MediaTek MT7628AN).
Hardware has two RJ45 ports but one physical device mtk_soc_eth eth0.
RJ45 ports are configured to be bridge (there are two VLANs for eth0.1 and eth0.2).
I have PC connected to eth0.1, and to eth0.2 there's Profinet device with webserver connected. The goal is to discover this device using PRONETA.
I am able to reach device's webserver so the bridge is functional. At the same time PRONETA doesn't detect the device. I wanted to sniff the traffic, I installed tcpdump on the router and saw that packet goes via eth0.1 and eth0.2 but then there's no response from Profinet device back on eth0.2 (IMG 1).
There's no possibility to sniff traffic on Profinet device. I wanted to check if the Profinet device sends back response. That's why I added additional PC as Machine-in-the-Middle to see what happens on the cable. But adding this PC made the Profinet device visible (sic!). I could see traffic on eth0.2 and see the device in the PRONETA (IMG 2).
Going back to first config - again I can't see the device.
In addition I installed luci-app-lldpd and here's the result (first setup - no MITM), I can detect both devices from the router. But I need to detect Profinet device from PC, so this doesn't help (IMG 3).
Why I can't detect the device in the first setup? Is it somehow related to VLAN functionality? Unfortunately, I do not have another openWRT device with two physical adapters (eth0 / eth1) to test it.
