Re: [sr-dev] [kamailio/kamailio] Path MTU handling - suggested solution for IPv6 (Issue #3119)

Fair enough. I will do what I can to help, but may not collect the confidence to do this in Kamailio, at least not without backup from a core developer.

I have started some tooling to measure these problems, [available here](https://gitlab.com/0cpm/mtugames/-/blob/master/veth/experiment.md).

* My observation that `veth` ethernet pairs (on Linux) could work around the problem is now falsified. * My next hope is to use `SO_REUSEADDR` or `SO_REUSEPORT` to open a secondary socket with a lower MTU, and fallback on that for resends.

I will continue to do these experiments outside of Kamailio, to avoid its complexity. If this works, it is most likely after integration with immediate resends.