Hi,
I have some ancient ABP devices running (since 2019 using RFM95). In the last months the traffic of 2 of these ABP devices is no longer appearing in the TTN console.
However I do see the traffic being send in the GW logs. Also when I configure these devices on my stand alone gateway the data is received correct.
Does anybody else have similar experience? (and maybe a solution :-))
Cheers
Did you reboot the devices at that point? If not, what is the uplink count for them?
FC (UL) was around 58.000 (so no overflow for the 16 bit counter). Yes I did reboot the device but FC is stored (also configured at TTN that FrameCounter is not checked).
That doesn’t not help with the MIC calculations as that uses the full 32 bits of the expected value (at least ttn by default does). However if your counter is still below 64k it doesn’t matter.
Can you try to decode and validate the uplink as seen in the gateway part of TTN console using the packet decoder?
Decoding via TTN works - see below.
(I did verify payload on another local standalone gateway / received ABP packet is decoded correctly).
Using Base64 to hex: Encode and decode bytes online — cryptii
Nothing comes to mind. Sorry, may-be someone else’s brain works better…
Thanks for thinking along Jac.
The only thing that crosses my mind is “TTN routing issue” … when that would be the case other people must also have had similar issues
Definitely an inferiour model of wetware, but with other talents, so:
What is the device/MCU? RFM95 implies LMIC, what version?
Unlikely, 99 times out of 10 it’s LMIC / ABP issues, either one or both.
Well, some of these devices have been running for over 4 years without any problem. Suddenly traffic does not show up at TTN while other standalone gw continues to receives ABP from this device.
Just made a fresh TTN ABP device configuration and hooked up device with similar hardware / software. Works like a charm.
My bet is still that something in the routing is mixed up (btw → stack was Ideetron’s).
Does that handle MAC commands? If not you are probably dos-sing the gateway. Check the number of downlinks for the device in the console to see if there are (almost) as many as uplinks.
For various values of not at all, at least not from the public repro.
As ever, would be easier to answer if we had an answer to what the device / MCU was as there are variations. And more details in the various statements:
Works like a charm with what? The standalone gateway or TTN?
What is the standalone gateway and how old is its firmware - if they are of the same vintage they will most likely be compatible.
Whereas TTSv3 is aiming for compliance so has expectations these days.
Given more info we can probably help as there are things that can be set on the console, but at about post 20 interest wanes in soliciting more info 
Similar device (which is up and running) shows the following 
This doesn’t give us anything to move this issue forward for you.
As mentioned: “fresh TTN ABP device configuration”. So running “like a charm” on TTN network. Of course also verified (positive) via the Stand Alone GW (running ChirpStack - installed sw version early 2022).
Funny thing is that the device, from which I do not see the traffic in the TTN console, is sending LoRa packets that can be decoded via TTN online decoder (see link from Jac above) and on the StandAlone Gateway.
Only solution which could work for now is to route the GW traffic to my our LoRa BE server and decode it there. However I am curious why it suddenly stops working, will try to collect some more details this week and post results here
It could have been a TTN configuration on TTS OS or Chirpstack but …
… you have Chirpstack and you’ve clarified it works on that and TTN.
Do the uplinks you see on the gateway appear on the gateway live data console?
Yes I do - see the device traffic on all GWs.
As a test I created 2 “fresh & identical devices” on my TTN account yesterday evening. Of the 2 devices I see all traffic on the gateways (once per hour). However when looking at the device level (TTN console inside the application):
Ideas?
I gave up 
Will move these devices to another LoRa backend/network.