[c-nsp] MTU and PMTUD

[Saku Ytti]

On Thu, 8 Dec 2022 at 11:25, Marcin Kurek <md.kurek at gmail.com> wrote:

> Interesting, but why would 'sh run' or 'write' raise an interrupt?
> Isn't this a branch in code that handles the CLI?

Maybe to access NVRAM? I don't know for sure, I didn't pursue it, I
just know I could observe it.

> I'm not sure if I'm reading it right - on the one hand, the interrupts are disabled, but on the other hand, some CLI commands actually raise them?

I don't know if IOS does polling or interrupt for NIC packets, but
there are tons of reasons to raise interrupt, not just NIC.

> Would you mind elaborating on why going above 4k would mean "newish features" and what are they?

https://www.rfc-editor.org/rfc/rfc8654.html

> So here CSR1kv is initiating the connection to XR box advertising MSS 8936 (as expected).
> However, peer MSS is 1240, which is not quite expected, considering XR config:

But it was [8936, 1240].min - so it was 'negotiated' here to the
smallest? If you change the 8936 end to 1239, then that will be used,
regardless who starts it.

-- 
  ++ytti