Traceroute gives different results to the same target

We have a mesh of about 30 nodes made of 13 GW connected via MQTT and 17 nodes connected via radio to the nearest GW, firmware kevel is 2.1.19 -2.1.23. Sometimes traceroute via Android App 2.1.20 works , sometimes don’t. I got a weird case addressing a RPT node connected via radio to his fellow GW in the MQTT lot in two cases: 1) directly from my GW / MQTT, 2) from another device of mines connected via radio to may GW / MQTT. The result is that in case 1) the target gives the correct route (my GW - target GW - fellow RPT node seen via radio). In case 2) the path is wrong since it shows the target RPT device seen from another GW which it does’nt see via radio nor via MQTT since it is’nt connected to the MQTT network. Here are the relevant screen shot from Android App.

A message can be delivered via different paths, because there is some randomness in the protocol that decides which node forwards a message. That’s why it might give different results to the same target.

However, it shouldn’t be that the route shows a wrong node. In this case you mean Torino-SantaRita GW 868 is wrong? Do you know for sure that IK1NAF-02_RPT_868_7600 cannot reach it via radio?

If you try again from IU2RPO_3508, do you get the same result?

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Actually in this moment I made 3 new attempst from IU2RPO_3508 and got two different wrong routing and one correct routing (the third attempt). The first attempt says the target is reached from a 433Mhz GW whilst the target works a 868Mhz, the second shows the routing thru another GW also not in the radio coverage from the target, the third attempt was the only one right since that GW is radio connected with the target. Then I tried a traceroute directly from my own GW and it worked nicely all the times.

If the 433MHz GW and the other GW not in radio coverage are connected to MQTT, it could end up in the route and in this way virtually ‘skip’ some nodes. At this point that seems to be the only possible reason.

Can you see the actual Node Numbers in the Traceroute messages from the Debug Panel?

Tgt NudeNum Id
3667359232 !da977600 IK1NAF-02_RPT_868_7600

Are there any nodes in the mesh that use a different encryption key (for the channel)? If so, they can still forward the packet but they will not show in the Traceroute.

Acually in the MQTT net there are GW either LONG_FAST or MEDIUM_FAST so there are two different keys according to these.