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

Tue Mar 12 18:09:32 UTC 2019

> From: Saku Ytti <saku at ytti.fi>
> Sent: Tuesday, March 12, 2019 6:01 PM
> 
> On Tue, Mar 12, 2019 at 7:55 PM <adamv0025 at netconsultings.com> wrote:
> 
> > This was on Trio and sorry I should have clarified we did test with default
> L3+L4 keys on MPLS labelled packets -default in Junos (as baseline).
> > And then repeated the test using flow labels -which forced Trio to ignore
> the L3+L4 keys and act solely on flow label.
> > PPS performance wise we couldn’t really tell the difference (was in the
> noise).
> 
> Are you sure we are talking about same thing. This thread is about 20bit IPv6
> header Flow Label. I feel like you're talking about FAT pseudowires?
> 
Yes right, but the lookup principle is the same either you look at IPv6 flow label or you look at the Entropy label.

> By default JNPR will in pseudowire transit look for IP keys, with or without
> FAT. Optionally it can look even with existence of CW.  You need to
> specifically ask it not to look for IP keys in pseudowires or add CW (and not
> explicitly tell it to look).
> 
We didn't use FAT PWs, but rather entropy labels for VPNv4 traffic.

adam