7 ms·

This is a little weird for me: Using Cloudflare's 1.1.1.1: ~> curl -s --doh-url https://cloudflare-dns.com/dns-query https://mensura.cdn-apple.com/api/v1/gm

This is a little weird for me: Using Cloudflare's 1.1.1.1: ~> curl -s --doh-url https://cloudflare-dns.com/dns-query https://mensura.cdn-apple.com/api/v1/gm/config | jq -r .test_endpoint sgsin3-edge-bx-008.aaplimg.com PING sgsin3-edge-bx-008.b.aaplimg.com (17.253.61.15) 56(84) bytes of data. 64 bytes from sgsin3-edge-bx-008.b.aaplimg.com (17.253.61.15): icmp_seq=1 ttl=52 time=74.2 ms If I use 8.8.8.8: ~> curl -s --doh-url https://dns.google/dns-query https://mensura.cdn-apple.com/api/v1/gm/config | jq -r .test_endpoint hkhkg1-edge-bx-007.aaplimg.com ~> ping hkhkg1-edge-bx-007.aaplimg.com PING hkhkg1-edge-bx-007.aaplimg.com (17.253.85.13) 56(84) bytes of data. 64 bytes from hkhkg1-edge-bx-007.aaplimg.com (17.253.85.13): icmp_seq=1 ttl=54 time=107 ms Seems like I'm two different PoPs depending on which DNS I'm using.

dweekly 3y ago
From the article: Apple's test_endpoint changes on each request, selecting a different nearby server to reduce latency and distributing their server load.
detaro 3y ago
why is that weird?
lxgr 3y ago
Where are you actually located? 1.1.1.1 does not support the EDNS client subnet header [1], which means that practically, the CDN's DNS server will see your request as originating from your nearest 1.1.1.1 resolver. 8.8.8.8 does, so if the CDN evaluates it, you might get a better match (or a worse one!) [1] https://developers.cloudflare.com/1.1.1.1/faq/#does-1.1.1.1-send-edns-client-subnet-header https://developers.cloudflare.com/1.1.1.1/faq/#does-1.1.1.1-...
- miyuru 3y ago
  EDNS makes a huge difference as many CDNS still use it. Here is a test I did 4 years back. https://blog.miyuru.lk/edns-geo-table-2019/ https://blog.miyuru.lk/edns-geo-table-2019/ I have a tinfoil-hat theory that CF removed EDNS support to make other CDNs slow and make their own CDN look good, but if there's a CF POP nearby it does not make much difference.

dweekly 3y ago

From the article: Apple's test_endpoint changes on each request, selecting a different nearby server to reduce latency and distributing their server load.

detaro 3y ago

why is that weird?

lxgr 3y ago

Where are you actually located? 1.1.1.1 does not support the EDNS client subnet header [1], which means that practically, the CDN's DNS server will see your request as originating from your nearest 1.1.1.1 resolver. 8.8.8.8 does, so if the CDN evaluates it, you might get a better match (or a worse one!) [1] https://developers.cloudflare.com/1.1.1.1/faq/#does-1.1.1.1-send-edns-client-subnet-header https://developers.cloudflare.com/1.1.1.1/faq/#does-1.1.1.1-...

miyuru 3y ago
EDNS makes a huge difference as many CDNS still use it. Here is a test I did 4 years back. https://blog.miyuru.lk/edns-geo-table-2019/ https://blog.miyuru.lk/edns-geo-table-2019/ I have a tinfoil-hat theory that CF removed EDNS support to make other CDNs slow and make their own CDN look good, but if there's a CF POP nearby it does not make much difference.