This is another for the record type posts that may be useful in future reference/discussions. Feel free to discuss here if you would like or just ignore it.
Executive summary: Global anycast DNS providers
Over the years there have been a few topics along the lines of:
- Why is my server getting requests from outside my zone
- Why isn’t my server included in zones other than where I put it
- How does the pool distribute requests to clients
- Other similar topics
Side note: How did I find this? Do a number of DNS requests from a number of locations in Asia and count the number of unique ip addresses returned = 809. The pool reports Asia currently has 611 servers active.
Some examples of the results are below. The “situation” seems to be happening across all the global DNS anycast providers. It may be they share the cache across locations or at the time of the request the DNS query was routed to a different country to be answered. It is what it is.
Note that the ip addresses grepped for are all in the “@ north-america US” zone but are being handed out to Asia clients asking for Asia ip addresses. I guess that the same happens in other zones/regions. I am NOT saying the is a problem that has to be fixed but I am saying that this should be taken into consideration in future discussions of why the world is not working the way you may expect it to work.
$ ntp-pcr --headers (for below csv line)
1 Timestamp,
2 Tested status,
3 Location string,
4 DNS server used,
5 Hostname asked for,
6 IP address returned,
7 Server Stratum,
8 Reference ID as a string,
9 Leap indicator,
10 Min Error in secs,
11 Root Dispersion in secs,
12 Root Delay in secs,
13 Root Distance in secs,
14 Round trip time in secs,
15 Clock offset in secs,
16 Absolute clock offset in mSec
$ zcat *.gz | grep Tested_OK | grep 2602:81c:1000:2::606
1789525379, Tested_OK, in-bom-aws, 2606:4700:4700::1111, 2.pool.ntp.org, 2602:81c:1000:2::606, 2, 153.153.36.115, 0, 0.000000000, 0.000625610, 0.007980347, 0.128143119, 0.247054672, 0.006837716, 6
$ zcat *.gz | grep Tested_OK | grep 2600:3c06::2000:a7ff:fe46:9a62
1789521834, Tested_OK, sg-sin-ovhcloud, 8.8.8.8, 2.pool.ntp.org, 2600:3c06::2000:a7ff:fe46:9a62, 5, 168.61.215.74, 0, 0.000000000, 0.010665894, 0.009262085, 0.128716157, 0.226838441, 0.009561919, 9
$ zcat *.gz | grep Tested_OK | grep 66.118.230.14
1789548156, Tested_OK, in-bom-vultr, 1.1.1.1, 2.pool.ntp.org, 66.118.230.14, 2, 216.239.35.4, 0, 0.000000000, 0.032592773, 0.012298584, 0.152220927, 0.226957725, -0.069197194, 69
1789559001, Tested_OK, in-bom-vultr, 1.1.1.1, 2.pool.ntp.org, 66.118.230.14, 2, 216.239.35.0, 0, 0.000000000, 0.025802612, 0.012313843, 0.147833365, 0.231747663, -0.069819516, 69
$ zcat *.gz | grep Tested_OK | grep 23.186.168.126
1789524177, Tested_OK, ph-mnl-lightnode, 9.9.9.9, pool.ntp.org, 23.186.168.126, 2, 132.163.96.4, 0, 0.000000000, 0.000900269, 0.034500122, 0.125499118, 0.214697576, -0.009633393, 9
1789542148, Tested_OK, in-bom-vultr, 1.1.1.1, 2.pool.ntp.org, 159.223.204.192, 3, 23.186.168.126, 0, 0.000000000, 0.001403809, 0.056777954, 0.152215556, 0.244845540, -0.001183121, 1
1789557785, Tested_OK, in-bom-aws, 2606:4700:4700::1111, 2.pool.ntp.org, 2604:a880:4:1d0:0:3:7100:b000, 3, 23.186.168.126, 0, 0.000000000, 0.001617432, 0.056838989, 0.160658474, 0.261243095, -0.008597277, 8
1789561356, Tested_OK, ph-mnl-lightnode, 9.9.9.9, pool.ntp.org, 23.186.168.126, 2, 132.163.96.4, 0, 0.000000000, 0.001358032, 0.034362793, 0.118660371, 0.200241885, 0.004385655, 4
1789563811, Tested_OK, ph-mnl-lightnode, 9.9.9.9, pool.ntp.org, 159.223.204.192, 3, 23.186.168.126, 0, 0.000000000, 0.001464844, 0.057266235, 0.155731520, 0.251267117, 0.008480117, 8
1789578232, Tested_OK, cl-scl-vultr, 9.9.9.9, 2.pool.ntp.org, 23.186.168.126, 2, 132.163.96.4, 0, 0.000000000, 0.000732422, 0.034240723, 0.104589778, 0.173473990, 0.009959997, 9