Re: Facebook post-mortems...

[Tom Beecher <beecher () beecher cc>]

> People keep repeating this but I don't think it's true.

My comment is solely sourced on my direct observations on my network, maybe
30-45 minutes in.

Everything except a few /24s disappeared from DFZ providers, but I still
heard those prefixes from direct peerings. There was no disaggregation that
I saw, just the big stuff gone. This was consistent over 5 continents from
my viewpoints.

Others may have seen different things at different times. I do not run an
eyeball so I had no need to continually monitor.

On Tue, Oct 5, 2021 at 10:22 AM Niels Bakker <niels=nanog () bakker net> wrote:

> * telescope40 () gmail com (Lou D) [Tue 05 Oct 2021, 15:12 CEST]:
> > Facebook stopped announcing the vast majority of their IP space to
> > the DFZ during this.
>
> People keep repeating this but I don't think it's true.
>
> It's probably based on this tweet:
> https://twitter.com/ryan505/status/1445118376339140618
>
> but that's an aggregate adding up prefix counts from many sessions.
> The total number of hosts covered by those announcements didn't vary
> by nearly as much, since to a significant extent it were more specifics
> (/24) of larger prefixes (e.g. /17) that disappeared, while those /17s
> stayed.
>
> (There were no covering prefixes for WhatsApp's NS addresses so those
> were completely unreachable from the DFZ.)
>
>
>         -- Niels.