ESP32 Forum

Is there any way to know if a p2p packet has been dropped?

esp_mesh_send does not fail if the p2p node address becomes undeliverable.

In my application, leaf node A will send periodic messages to leaf node B. A & B may or may not have a common parent. If B disappears, is there any way node A can know this except for a message sent out by the root node in response to the MESH_EVENT_ROUTING_TABLE_REMOVE event?

Also, where do these undeliverable packets end up? Is there a buffer that they fill that needs to be checked and flushed periodically?

Thank you.

MESH_TOS_P2P packet will return success if the packet has been sent to the next-hop.
In your case, A node didn't know whether B node is in the same mesh network. The routing table of a particular node will consist of the MAC addresses of all nodes within the particular node’s subnetwork.
Refer to https://docs.espressif.com/projects/esp ... ing-tables
We haventn't complete the function MESH_TOS_E2E, so you might need to do it in your application.

I see...

So, the fact that the MAC is not in the root's routing table is in fact the final determinate of if a packet is deliverable. Cool.

But is there some hook into this process that would allow me to take action when this happens to a packet? I can hack it out in other (ugly) ways, but it would be really great if there was some sort of hook (event, callback, whatever) that I can use to know that the packet has been deemed undeliverable and has been dropped.

B

To be clear... what I would like is some sort of hook on root... so that when root drops the packet, it can read the packet and let the node that sent it know that the destination node is no longer out there.

Thanks.