RE: Facebook post-mortems...

[Jean St-Laurent via NANOG <nanog () nanog org>]

I agree to resolve non-routable address doesn’t bring you a working service.

 

I thought a few networks were still reachable like their MX or some DRP networks.

 

Thanks for the update

Jean

 

From: Tom Beecher <beecher () beecher cc> 
Sent: October 5, 2021 8:33 AM
To: Jean St-Laurent <jean () ddostest me>
Cc: Jeff Tantsura <jefftant.ietf () gmail com>; William Herrin <bill () herrin us>; NANOG <nanog () nanog org>
Subject: Re: Facebook post-mortems...

 

Maybe withdrawing those routes to their NS could have been mitigated by having NS in separate entities.

 

Assuming they had such a thing in place , it would not have helped. 

 

Facebook stopped announcing the vast majority of their IP space to the DFZ during this. So even they did have an offnet 
DNS server that could have provided answers to clients, those same clients probably wouldn't have been able to connect 
to the IPs returned anyways. 

 

If you are running your own auths like they are, you likely view your public network reachability as almost bulletproof 
and that it will never disappear. Which is probably true most of the time. Until yesterday happens and the 9's in your 
reliability percentage change to 7's. 

 

On Tue, Oct 5, 2021 at 8:10 AM Jean St-Laurent via NANOG <nanog () nanog org <mailto:nanog () nanog org> > wrote:

Maybe withdrawing those routes to their NS could have been mitigated by having NS in separate entities.

Let's check how these big companies are spreading their NS's.

$ dig +short facebook.com <http://facebook.com>  NS
d.ns.facebook.com <http://d.ns.facebook.com> .
b.ns.facebook.com <http://b.ns.facebook.com> .
c.ns.facebook.com <http://c.ns.facebook.com> .
a.ns.facebook.com <http://a.ns.facebook.com> .

$ dig +short google.com <http://google.com>  NS
ns1.google.com <http://ns1.google.com> .
ns4.google.com <http://ns4.google.com> .
ns2.google.com <http://ns2.google.com> .
ns3.google.com <http://ns3.google.com> .

$ dig +short apple.com <http://apple.com>  NS
a.ns.apple.com <http://a.ns.apple.com> .
b.ns.apple.com <http://b.ns.apple.com> .
c.ns.apple.com <http://c.ns.apple.com> .
d.ns.apple.com <http://d.ns.apple.com> .

$ dig +short amazon.com <http://amazon.com>  NS
ns4.p31.dynect.net <http://ns4.p31.dynect.net> .
ns3.p31.dynect.net <http://ns3.p31.dynect.net> .
ns1.p31.dynect.net <http://ns1.p31.dynect.net> .
ns2.p31.dynect.net <http://ns2.p31.dynect.net> .
pdns6.ultradns.co.uk <http://pdns6.ultradns.co.uk> .
pdns1.ultradns.net <http://pdns1.ultradns.net> .

$ dig +short netflix.com <http://netflix.com>  NS
ns-1372.awsdns-43.org <http://ns-1372.awsdns-43.org> .
ns-1984.awsdns-56.co.uk <http://ns-1984.awsdns-56.co.uk> .
ns-659.awsdns-18.net <http://ns-659.awsdns-18.net> .
ns-81.awsdns-10.com <http://ns-81.awsdns-10.com> .

Amnazon and Netflix seem to not keep their eggs in the same basket. From a first look, they seem more resilient than 
facebook.com <http://facebook.com> , google.com <http://google.com>  and apple.com <http://apple.com> 

Jean

-----Original Message-----
From: NANOG <nanog-bounces+jean=ddostest.me () nanog org <mailto:ddostest.me () nanog org> > On Behalf Of Jeff Tantsura
Sent: October 5, 2021 2:18 AM
To: William Herrin <bill () herrin us <mailto:bill () herrin us> >
Cc: nanog () nanog org <mailto:nanog () nanog org> 
Subject: Re: Facebook post-mortems...

129.134.30.0/23 <http://129.134.30.0/23> , 129.134.30.0/24 <http://129.134.30.0/24> , 129.134.31.0/24 
<http://129.134.31.0/24> . The specific routes covering all 4 nameservers (a-d) were withdrawn from all FB peering at 
approximately 15:40 UTC.

Cheers,
Jeff

> On Oct 4, 2021, at 22:45, William Herrin <bill () herrin us <mailto:bill () herrin us> > wrote:
>
> On Mon, Oct 4, 2021 at 6:15 PM Michael Thomas <mike () mtcc com <mailto:mike () mtcc com> > wrote:
> > They have a monkey patch subsystem. Lol.
>
> Yes, actually, they do. They use Chef extensively to configure 
> operating systems. Chef is written in Ruby. Ruby has something called 
> Monkey Patches. This is where at an arbitrary location in the code you 
> re-open an object defined elsewhere and change its methods.
>
> Chef doesn't always do the right thing. You tell Chef to remove an RPM 
> and it does. Even if it has to remove half the operating system to 
> satisfy the dependencies. If you want it to do something reasonable, 
> say throw an error because you didn't actually tell it to remove half 
> the operating system, you have a choice: spin up a fork of chef with a 
> couple patches to the chef-rpm interaction or just monkey-patch it in 
> one of your chef recipes.
>
> Regards,
> Bill Herrin
>
> --
> William Herrin
> bill () herrin us <mailto:bill () herrin us> 
> https://bill.herrin.us/