In any Wi-Fi firmware that I write with nRF Connect SDK I get this error message in my console logs:
<err> net_icmpv6: ICMPv6 handling failure (-2)
This happens in every app I've run, including all the code in your Wi-Fi Fundamentals course, samples and my own firmware. It happens due to incoming messages from my network, even when my app is sitting idle (not sending anything). I sometimes get 1 or 2 per second, and other times it is many seconds between these errors.
I traced it down a little and it appears to be from incoming ICMP messages that the Zephyr or Nordic firmware doesn't know how to deal with.
I am using v2.6.1 of the SDK.
Do you know what this error message means, and how to get rid of it?
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I turned on debug logging in the icmpv6.c module and it looks like ICMPv6 input that triggers the error is an ICMPv6 Redirect Message type 137:
I traced the code out a bit with the debugger, and when a redirect message comes in and icmp_call_handlers() in zephyr/subsys/net/ip/icmp.c is called, it looks through the list of handlers for different ICMP message types and doesn't find one for Redirect type 137.
Is this handler something I have to enable via a CONFIG option or something?