ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms

Tue Mar 5 06:18:16 UTC 2019

On 5/Mar/19 00:25, Mark Andrews wrote:

>
> Then Cloudflare should negotiate MSS’s that don’t generate PTB’s if
> they have installed broken ECMP devices.  The simplest way to do that
> is to set the interface MTUs to 1280 on all the servers.  Why should
> the rest of the world have to put up with their inability to purchase
> devices that work with RFC compliant data streams.

I've had this issue with cdnjs.cloudflare.com for the longest time at my
house. But as some of you may recall, my little unwanted TCP MSS hack
for IPv6 last weekend fixed that issue for me.

Not ideal, and I so wish IPv6 would work as designed, but...

Mark.