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A comment on What happens when you update your DNS. Parent comment

Re:What happens when you update your DNS by LogicX on Monday June 22, 2020 @06:55PM (#23607897)
Just to add to the discussion -- 'whats happening in the background' -- more specifically is your operating system's stub resolver.

So when you ask for www.amazon.com it ends up making multiple DNS lookups, as www.amazon.com is a CNAME record.

Nothing about this CNAME lookup gets passed back up the stack to your application; you just get that end-result: the IP address.

host www.amazon.com www.amazon.com is an alias for tp.47cf2c8c9-frontier.amazon.com. tp.47cf2c8c9-frontier.amazon.com is an alias for www.amazon.com.edgekey.net. www.amazon.com.edgekey.net is an alias for e15316.e22.akamaiedge.net. e15316.e22.akamaiedge.net has address 23.204.68.114

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Re:What happens when you update your DNS by chrisweekly on Monday June 22, 2020 @08:03PM (#23608442)
Am I the only one who finds it strange that Amazon uses Akamai instead of Cloudfront?
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Re:What happens when you update your DNS by forbiddenlake on Monday June 22, 2020 @10:22PM (#23609325)
It varies. For example, for www.amazon.com, I get www.amazon.com -> tp.47cf2c8c9-frontier.amazon.com. -> d3ag4hukkh62yn.cloudfront.net.
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Re:What happens when you update your DNS by _jal on Monday June 22, 2020 @08:28PM (#23608648)
Why is that?

(My first thought was, wow, surprised they outsource that.)

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Re:What happens when you update your DNS by Legogris on Monday June 22, 2020 @11:18PM (#23609587)
I'd wager at least part of it is the same reason many companies use CloudFront: Separate point of failure in case of downtime at the AWS side, some one else shouldering DDoS.
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Re:What happens when you update your DNS by blyry on Monday June 22, 2020 @09:27PM (#23609036)
Pure speculation, but probably the same reason they ran Oracle for so long -- not many cdn providers when amazon.com launched. Afaik akamai still has one of the biggest edge networks of all the providers.
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Re:What happens when you update your DNS by MaxBarraclough on Tuesday June 23, 2020 @05:58AM (#23611844)
I asked the same question 7 days ago: https://news.ycombinator.com/item?id=23537135
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