Hello everybody! More details follow, but I start with: YES, I do have default-forwarding=yes!
One WiFi device connected to a MikroTik 951Ui-2HnD running RouterOS 6.38.5 cannot be accessed from ANY other device connected to the same 951Ui-2HnD, but works fine with ANY device connected to one Ethernet ports of 951Ui-2HnD.
I made several cross-checks and I finally determined that 3 units and PING are enough to see the problem:
1 Mikrotik 951Ui-2HnD (address 10.3.50.11)
1 ESP8266 (address 10.3.50.11)
1 Linux box (WiFi) (address 10.3.50.54)
OR the same laptop:
1 Linux box (ethernet)(address 10.3.50.59)
I captured and decoded “on the air” using a 4th box running Wireshark and “Monitor Mode” active. The problem shows at ARP level: on WiFi it seems ESP is lazy to answer and the Linux Box doesn’t like the answer. If the Linux Box is connected to LAN and the ESP is the only device in WiFi, ESP answer immediately and its answer is immediately understood.
In the file l59e21.pcapng, we can see a working ARP around line 221-249. In the file l54e21 we see a “failing” (??) ARP, at lines 911-913. Under my point of view, packet 913 of the second file is identical to packet 249 of the first one, save for the Linux IP address and MAC, of course.
I guess the problem may lie in the lower level packets that I am not able to understand.
Some notes:
Two Linux Boxes in WiFi work fine between them.
Android is intermittent: never works with ESP, with Linux sometimes connects, sometimes doesn’t: no trace at the moment.
I connected the same Linux box to a different WiFi Access Point, connected via LAN to the MikroTik and, in this case, it can ping ESP, exactly as when it is connected via LAN - no trace at the moment.
In the MikroTik configuration I do have: default-forwarding=yes
I attach the two pcap files and the router configuration.
I hope someone can give a good suggestion: I am fighting the problem by 2 weeks and I am at a dead point!
pcap.zip (244 KB)
rescas.rsc (60.3 KB)