Better description of what happened

[Michael Thomas <mike () mtcc com>]

This bit posted by Randy might get lost in the other thread, but it 
appears that their DNS withdraws BGP routes for prefixes that they can't 
reach or are flaky it seems. Apparently that goes for the prefixes that 
the name servers are on too. This caused internal outages too as it 
seems they use their front facing DNS just like everybody else.

Sounds like they might consider having at least one split horizon server 
internally. Lots of fodder here.

Mike

On 10/5/21 11:11 AM, Randy Monroe wrote:
> Updated: 
> https://engineering.fb.com/2021/10/05/networking-traffic/outage-details/ 
> <https://engineering.fb.com/2021/10/05/networking-traffic/outage-details/>
>
> On Tue, Oct 5, 2021 at 1:26 PM Michael Thomas <mike () mtcc com 
> <mailto:mike () mtcc com>> wrote:
>
>
>     On 10/5/21 12:17 AM, Carsten Bormann wrote:
>     > On 5. Oct 2021, at 07:42, 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.
>     > While Ruby indeed has a chain-saw (read: powerful, dangerous,
>     still the tool of choice in certain cases) in its toolkit that is
>     generally called “monkey-patching”, I think Michael was actually
>     thinking about the “chaos monkey”,
>     > https://en.wikipedia.org/wiki/Chaos_engineering#Chaos_Monkey
>     <https://en.wikipedia.org/wiki/Chaos_engineering#Chaos_Monkey>
>     > https://netflix.github.io/chaosmonkey/
>     <https://netflix.github.io/chaosmonkey/>
>
>     No, chaos monkey is a purposeful thing to induce corner case
>     errors so
>     they can be fixed. The earlier outage involved a config sanitizer
>     that
>     screwed up and then pushed it out. I can't get my head around why
>     anybody thought that was a good idea vs rejecting it and making
>     somebody
>     fix the config.
>
>     Mike
>
>
>
>
> --
>
> Randy Monroe
>
> Network Engineering
>
> Uber <https://uber.com/>
>
>
>         
>         
>