Re: Facebook post-mortems...

[Mark Tinka <mark@tinka.africa>]

On 10/5/21 14:58, Jean St-Laurent wrote:
> If your NS are in 2 separate entities, you could still resolve your MX/A/AAAA/NS.
>
> Look how Amazon is doing it.
>
> dig +short amazon.com NS
> ns4.p31.dynect.net.
> ns3.p31.dynect.net.
> ns1.p31.dynect.net.
> ns2.p31.dynect.net.
> pdns6.ultradns.co.uk.
> pdns1.ultradns.net.
>
> They use dyn DNS from Oracle and ultradns. 2 very strong network of anycast DNS servers.
>
> Amazon would have not been impacted like Facebook yesterday. Unless ultradns and Oracle have their DNS servers hosted in 
> Amazon infra? I doubt that Oracle has dns hosted in Amazon, but it's possible.
>
> Probably the management overhead to use 2 different entities for DNS is not financially viable?

So I'm not worried about DNS stability when split across multiple 
physical entities.

I'm talking about the actual services being hosted on a single network 
that goes bye-bye like what we saw yesterday.

All the DNS resolution means diddly, even if it tells us that DNS is not 
the issue.

Mark.