Ask HN: Why isn't multivalue answer DNS used outside Amazon?

#1

Post by dsjfalksjdflksa » Thu, Jan 28, 2021, 6:17 AM UTC

Multivalue answer dns is used widely at Amazon (internally and as an aws offering), but it seems like other providers aren't offering this service.

* https://aws.amazon.com/premiumsupport/knowledge-center/multivalue-versus-simple-policies/

* https://aws.amazon.com/about-aws/whats-new/2017/06/amazon-route-53-announces-support-for-multivalue-answers-in-response-to-dns-queries/

Does anyone know about why this practice is not widespread outside of Amazon? Besides that, any technical references or analysis about multivalue answer DNS would be helpful.

Re: Ask HN: Why isn't multivalue answer DNS used outside Amazon?

#2

Post by coolspot » Thu, Jan 28, 2021, 8:15 AM UTC

It is widespread for high-load highly-available distributed sites.

Amazon multivalue response is just a short TTL DNS record on a DNS server that returns one address from dynamic set of healthy IPs.

https://github.com/crohr/ebarnouflant/issues/19

Re: Ask HN: Why isn't multivalue answer DNS used outside Amazon?

#3

Post by ktpsns » Thu, Jan 28, 2021, 8:15 AM UTC

DNS Round robin is as standard practice. Just "dig google.com" in your terminal and your DNS provider will certainly spit out multiple IPs.

https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/re... also mentions a "health" column. Thats beyond the scope of a public world wide DNS with caching, in my opinion.