So here's a weird question: Supposing companies multi-home for DNS, or whatever other essential service, via multiple service providers.
Whatever multi-home means, why can't there just be one service provider that does that? And are we sure that these service providers aren't already doing that as best we might hope for? (For instance, Amazon already has multiple zones, etc.)
I suppose the one thing this can't protect against is some sort of political (broadly defined) threat related to the company itself.
> Whatever multi-home means, why can't there just be one service provider that does that?
Many of these outages are due to pushing broken artifacts or configuration to production.
A single provider can pretty easily offer geographic or network topological redundancy, but administrative and/or technological independence is pretty hard to achieve in a single company.
I mean, I guess what I'm saying is that in theory a single provider could purposely keep two different departments that manage their own artifacts independently.
I believe EasyDNS can automatically push DNS settings to Route53 to host DNS in AWS. Doesn't protect you from fat-fingering a change, but you should be resilient to either EasyDNS or Route53 going down.
Using multiple providers for mostly static DNS is easy, pick one as primary and AXFR to the other and notifications and whatever. Or it's not too hard to keep a zone file in source control and sync it to the providers.
Using multiple providers for fancy DNS, like only providing IPs that pass healthchecks or geotargetting users to datacenters gets pretty hard, because the different providers have similar capabilities, but no uniform interface, so you've either got to do it manually, or you have to build out your own abstraction that is probably limiting.
If possible, insourcing DNS makes the most sense to me, because if you can't keep your service online, it's not the worst if your DNS is offline; and if you can keep your service online, you probably won't mess up your DNS too badly.
Most CDNs offer huge incentives for sending them more traffic, a lot of time you end up in a contract obligated to handle X requests and Y gigabytes of traffic per month. But personally I believe you should never have a single provider for anything - particularly when it’s acceptable for a company to cut you off with no warning or recourse.
Whatever multi-home means, why can't there just be one service provider that does that? And are we sure that these service providers aren't already doing that as best we might hope for? (For instance, Amazon already has multiple zones, etc.)
I suppose the one thing this can't protect against is some sort of political (broadly defined) threat related to the company itself.