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@n1zyy
Last active June 16, 2024 18:07
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Apple NTP servers

Apple runs a fleet of stratum 1 NTP servers at time.apple.com. In my experience, ntpd/chronyd are very happy with them.

It looks like, instead of doing anycast, they maybe use DNS to steer you to the closest one.

time.apple.com is a CNAME for time-osx.g.aaplimg.com. Querying a handful of DNS servers, I've identified the following locations:

IP Hostname Location
17.253.2.125 usdal4-ntp-001.aaplimg.com. Dallas
17.253.2.253 usdal4-ntp-002.aaplimg.com. Dallas
17.253.4.125 ussjc2-ntp-001.aaplimg.com. San Jose
17.253.4.253 ussjc2-ntp-002.aaplimg.com. San Jose
17.253.6.125 usatl4-ntp-001.aaplimg.com. Atlanta
17.253.6.253 usatl4-ntp-002.aaplimg.com. Atlanta
17.253.12.125 usmia1-ntp-001.aaplimg.com. Miami
17.253.12.253 usmia1-ntp-002.aaplimg.com. Miami
17.253.14.123 usnyc3-ntp-003.aaplimg.com. NYC
17.253.14.125 usnyc3-ntp-001.aaplimg.com. NYC
17.253.14.251 usnyc3-ntp-004.aaplimg.com. NYC
17.253.14.253 usnyc3-ntp-002.aaplimg.com. NYC
17.253.16.125 usscz2-ntp-001.aaplimg.com. Santa Cruz?
17.253.16.253 usscz2-ntp-002.aaplimg.com. Santa Cruz?
17.253.18.125 brsao4-ntp-001.aaplimg.com. São Paulo
17.253.18.253 brsao4-ntp-002.aaplimg.com. São Paulo
17.253.20.125 usqas2-ntp-001.aaplimg.com. Ashburn, VA
17.253.20.253 usqas2-ntp-002.aaplimg.com. Ashburn, VA
17.253.24.125 uschi5-ntp-001.aaplimg.com. Chicago
17.253.24.253 uschi5-ntp-002.aaplimg.com. Chicago
17.253.26.125 uslax1-ntp-001.aaplimg.com. Los Angeles
17.253.26.253 uslax1-ntp-002.aaplimg.com. Los Angeles
17.253.28.125 usmes1-ntp-001.aaplimg.com. Mesa, Arizona
17.253.28.253 usmes1-ntp-002.aaplimg.com. Mesa, Arizona
17.253.30.125 ussea4-ntp-001.aaplimg.com. Seattle
17.253.30.253 ussea4-ntp-002.aaplimg.com. Seattle
17.253.34.123 uklon5-ntp-003.aaplimg.com. London
17.253.34.125 uklon5-ntp-001.aaplimg.com. London
17.253.34.251 uklon5-ntp-004.aaplimg.com. London
17.253.34.253 uklon5-ntp-002.aaplimg.com. London
17.253.38.125 sesto4-ntp-001.aaplimg.com. Stockholm
17.253.38.253 sesto4-ntp-002.aaplimg.com. Stockholm
17.253.52.125 nlams2-ntp-001.aaplimg.com. Amsterdam
17.253.52.253 nlams2-ntp-002.aaplimg.com. Amsterdam
17.253.54.123 defra1-ntp-003.aaplimg.com. Frankfurt
17.253.54.125 defra1-ntp-001.aaplimg.com. Frankfurt
17.253.54.251 defra1-ntp-004.aaplimg.com. Frankfurt
17.253.54.253 defra1-ntp-002.aaplimg.com. Frankfurt
17.253.66.125 ausyd2-ntp-001.aaplimg.com. Sydney
17.253.66.253 ausyd2-ntp-002.aaplimg.com. Sydney
17.253.68.123 jptyo5-ntp-003.aaplimg.com. Tokyo
17.253.68.125 jptyo5-ntp-001.aaplimg.com. Tokyo
17.253.68.251 jptyo5-ntp-004.aaplimg.com. Tokyo
17.253.68.253 jptyo5-ntp-002.aaplimg.com. Tokyo
17.253.74.125 jposa3-ntp-001.aaplimg.com. Osaka, Japan
17.253.74.253 jposa3-ntp-002.aaplimg.com. Osaka, Japan
17.253.82.125 sgsin3-ntp-001.aaplimg.com. Singapore
17.253.82.253 sgsin3-ntp-002.aaplimg.com. Singapore
17.253.84.123 hkhkg1-ntp-003.aaplimg.com. Hong Kong
17.253.84.125 hkhkg1-ntp-001.aaplimg.com. Hong Kong
17.253.84.251 hkhkg1-ntp-004.aaplimg.com. Hong Kong
17.253.84.253 hkhkg1-ntp-002.aaplimg.com. Hong Kong
17.253.106.125 dkblp1-ntp-001.aaplimg.com. Denmark
17.253.106.253 dkblp1-ntp-002.aaplimg.com. Denmark
17.253.108.125 frcch1-ntp-001.aaplimg.com. France
17.253.108.253 frcch1-ntp-002.aaplimg.com. France
17.253.110.125 zaisd1-ntp-001.aaplimg.com. South Africa
17.253.110.253 zaisd1-ntp-002.aaplimg.com. South Africa
17.253.114.125 krsel6-ntp-001.aaplimg.com. Seoul, Korea
17.253.114.253 krsel6-ntp-002.aaplimg.com. Seoul, Korea
17.253.116.125 twtpe2-ntp-001.aaplimg.com. Taipei
17.253.116.253 twtpe2-ntp-002.aaplimg.com. Taipei
17.253.122.125 rumow2-ntp-001.aaplimg.com. Moscow
17.253.122.253 rumow2-ntp-002.aaplimg.com. Moscow
@olegkonevarts
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olegkonevarts commented Jun 9, 2024

Hi, n1zyy! Thanks for this list.

It was interesting to explore it!

I rescanned the 17.253... pool of IPv4 addresses. Here is the latest information about these Apple NTP servers:

# IPv4 address (↓) Domain name(s)
8804 17.253.34.99 auper2-ntp-001.aaplimg.com
8836 17.253.34.131 auper2-ntp-002.aaplimg.com
16934 17.253.66.37 ausyd2-ntp-001.aaplimg.com
16942 17.253.66.45 ausyd2-ntp-002.aaplimg.com
2710 17.253.10.149 brsao4-ntp-001.aaplimg.com
2726 17.253.10.165 brsao4-ntp-002.aaplimg.com
18676 17.253.72.243 deber5-gslb-004.aaplimg.com; krseo1-ntp-002.aaplimg.com
3710 17.253.14.125 defra1-ntp-001.aaplimg.com
3838 17.253.14.253 defra1-ntp-002.aaplimg.com
3708 17.253.14.123 defra1-ntp-003.aaplimg.com
3836 17.253.14.251 defra1-ntp-004.aaplimg.com
27262 17.253.106.125 dkblp1-ntp-001.aaplimg.com
27390 17.253.106.253 dkblp1-ntp-002.aaplimg.com
27774 17.253.108.125 frcch1-ntp-001.aaplimg.com
27902 17.253.108.253 frcch1-ntp-002.aaplimg.com
21630 17.253.84.125 hkhkg1-ntp-001.aaplimg.com
21758 17.253.84.253 hkhkg1-ntp-002.aaplimg.com
21628 17.253.84.123 hkhkg1-ntp-003.aaplimg.com
21756 17.253.84.251 hkhkg1-ntp-004.aaplimg.com
4708 17.253.18.99 inbom5-ntp-001.aaplimg.com
4740 17.253.18.131 inbom5-ntp-002.aaplimg.com
19070 17.253.74.125 jposa3-ntp-001.aaplimg.com
19198 17.253.74.253 jposa3-ntp-002.aaplimg.com
17534 17.253.68.125 jptyo5-ntp-001.aaplimg.com
17662 17.253.68.253 jptyo5-ntp-002.aaplimg.com
17532 17.253.68.123 jptyo5-ntp-003.aaplimg.com
17660 17.253.68.251 jptyo5-ntp-004.aaplimg.com
17958 17.253.70.37 jptyo7-ntp-001.aaplimg.com
17966 17.253.70.45 jptyo7-ntp-002.aaplimg.com
29310 17.253.114.125 krsel6-ntp-001.aaplimg.com
29438 17.253.114.253 krsel6-ntp-002.aaplimg.com
18674 17.253.72.241 krseo1-ntp-001.aaplimg.com
13438 17.253.52.125 ntp.euro.apple.com; nlams2-ntp-001.aaplimg.com
13566 17.253.52.253 ntp.euro.apple.com; nlams2-ntp-002.aaplimg.com
9854 17.253.38.125 sesto4-ntp-001.aaplimg.com
9982 17.253.38.253 sesto4-ntp-002.aaplimg.com
15486 17.253.60.125 sgsin3-ntp-001.aaplimg.com
15614 17.253.60.253 sgsin3-ntp-002.aaplimg.com
29822 17.253.116.125 twtpe2-ntp-001.aaplimg.com
29950 17.253.116.253 twtpe2-ntp-002.aaplimg.com
7422 17.253.28.253 uklon5-ntp-002.aaplimg.com; usmes1-ntp-002.aaplimg.com; ntp.euro.apple.com
7292 17.253.28.123 uklon5-ntp-003.aaplimg.com
7420 17.253.28.251 uklon5-ntp-004.aaplimg.com
1574 17.253.6.37 usatl4-ntp-001.aaplimg.com
1582 17.253.6.45 usatl4-ntp-002.aaplimg.com
6782 17.253.26.125 uschi5-ntp-001.aaplimg.com
6910 17.253.26.253 uschi5-ntp-002.aaplimg.com
6780 17.253.26.123 uschi5-ntp-003.aaplimg.com
6908 17.253.26.251 uschi5-ntp-004.aaplimg.com
32382 17.253.126.125 usdal4-ntp-001.aaplimg.com
32510 17.253.126.253 usdal4-ntp-002.b.aaplimg.com; usdal4-ntp-002.aaplimg.com
13924 17.253.54.99 ushnl2-ntp-001.aaplimg.com
13956 17.253.54.131 ushnl2-ntp-002.aaplimg.com
21118 17.253.82.125 uslax1-ntp-001.aaplimg.com
21246 17.253.82.253 uslax1-ntp-002.aaplimg.com
7294 17.253.28.125 usmes1-ntp-001.aaplimg.com; ntp.euro.apple.com; uklon5-ntp-001.aaplimg.com
3110 17.253.12.37 usmia1-ntp-001.aaplimg.com
3118 17.253.12.45 usmia1-ntp-002.aaplimg.com
638 17.253.2.125 usnyc3-ntp-001.aaplimg.com
766 17.253.2.253 usnyc3-ntp-002.aaplimg.com
636 17.253.2.123 usnyc3-ntp-003.aaplimg.com
764 17.253.2.251 usnyc3-ntp-004.aaplimg.com
5246 17.253.20.125 usqas2-ntp-001.aaplimg.com
5374 17.253.20.253 usqas2-ntp-002.aaplimg.com
4222 17.253.16.125 usscz2-ntp-001.aaplimg.com
4350 17.253.16.253 usscz2-ntp-002.aaplimg.com
7806 17.253.30.125 ussea4-ntp-001.aaplimg.com
7934 17.253.30.253 ussea4-ntp-002.aaplimg.com
1150 17.253.4.125 ussjc2-ntp-001.aaplimg.com
1278 17.253.4.253 ussjc2-ntp-002.aaplimg.com
28286 17.253.110.125 zaisd1-ntp-001.aaplimg.com
28414 17.253.110.253 zaisd1-ntp-002.aaplimg.com
(↓) # IPv4 address Domain name(s)
636 17.253.2.123 usnyc3-ntp-003.aaplimg.com
638 17.253.2.125 usnyc3-ntp-001.aaplimg.com
764 17.253.2.251 usnyc3-ntp-004.aaplimg.com
766 17.253.2.253 usnyc3-ntp-002.aaplimg.com
1150 17.253.4.125 ussjc2-ntp-001.aaplimg.com
1278 17.253.4.253 ussjc2-ntp-002.aaplimg.com
1574 17.253.6.37 usatl4-ntp-001.aaplimg.com
1582 17.253.6.45 usatl4-ntp-002.aaplimg.com
2710 17.253.10.149 brsao4-ntp-001.aaplimg.com
2726 17.253.10.165 brsao4-ntp-002.aaplimg.com
3110 17.253.12.37 usmia1-ntp-001.aaplimg.com
3118 17.253.12.45 usmia1-ntp-002.aaplimg.com
3708 17.253.14.123 defra1-ntp-003.aaplimg.com
3710 17.253.14.125 defra1-ntp-001.aaplimg.com
3836 17.253.14.251 defra1-ntp-004.aaplimg.com
3838 17.253.14.253 defra1-ntp-002.aaplimg.com
4222 17.253.16.125 usscz2-ntp-001.aaplimg.com
4350 17.253.16.253 usscz2-ntp-002.aaplimg.com
4708 17.253.18.99 inbom5-ntp-001.aaplimg.com
4740 17.253.18.131 inbom5-ntp-002.aaplimg.com
5246 17.253.20.125 usqas2-ntp-001.aaplimg.com
5374 17.253.20.253 usqas2-ntp-002.aaplimg.com
6780 17.253.26.123 uschi5-ntp-003.aaplimg.com
6782 17.253.26.125 uschi5-ntp-001.aaplimg.com
6908 17.253.26.251 uschi5-ntp-004.aaplimg.com
6910 17.253.26.253 uschi5-ntp-002.aaplimg.com
7292 17.253.28.123 uklon5-ntp-003.aaplimg.com
7294 17.253.28.125 usmes1-ntp-001.aaplimg.com; ntp.euro.apple.com; uklon5-ntp-001.aaplimg.com
7420 17.253.28.251 uklon5-ntp-004.aaplimg.com
7422 17.253.28.253 uklon5-ntp-002.aaplimg.com; usmes1-ntp-002.aaplimg.com; ntp.euro.apple.com
7806 17.253.30.125 ussea4-ntp-001.aaplimg.com
7934 17.253.30.253 ussea4-ntp-002.aaplimg.com
8804 17.253.34.99 auper2-ntp-001.aaplimg.com
8836 17.253.34.131 auper2-ntp-002.aaplimg.com
9854 17.253.38.125 sesto4-ntp-001.aaplimg.com
9982 17.253.38.253 sesto4-ntp-002.aaplimg.com
13438 17.253.52.125 ntp.euro.apple.com; nlams2-ntp-001.aaplimg.com
13566 17.253.52.253 ntp.euro.apple.com; nlams2-ntp-002.aaplimg.com
13924 17.253.54.99 ushnl2-ntp-001.aaplimg.com
13956 17.253.54.131 ushnl2-ntp-002.aaplimg.com
15486 17.253.60.125 sgsin3-ntp-001.aaplimg.com
15614 17.253.60.253 sgsin3-ntp-002.aaplimg.com
16934 17.253.66.37 ausyd2-ntp-001.aaplimg.com
16942 17.253.66.45 ausyd2-ntp-002.aaplimg.com
17532 17.253.68.123 jptyo5-ntp-003.aaplimg.com
17534 17.253.68.125 jptyo5-ntp-001.aaplimg.com
17660 17.253.68.251 jptyo5-ntp-004.aaplimg.com
17662 17.253.68.253 jptyo5-ntp-002.aaplimg.com
17958 17.253.70.37 jptyo7-ntp-001.aaplimg.com
17966 17.253.70.45 jptyo7-ntp-002.aaplimg.com
18674 17.253.72.241 krseo1-ntp-001.aaplimg.com
18676 17.253.72.243 deber5-gslb-004.aaplimg.com; krseo1-ntp-002.aaplimg.com
19070 17.253.74.125 jposa3-ntp-001.aaplimg.com
19198 17.253.74.253 jposa3-ntp-002.aaplimg.com
21118 17.253.82.125 uslax1-ntp-001.aaplimg.com
21246 17.253.82.253 uslax1-ntp-002.aaplimg.com
21628 17.253.84.123 hkhkg1-ntp-003.aaplimg.com
21630 17.253.84.125 hkhkg1-ntp-001.aaplimg.com
21756 17.253.84.251 hkhkg1-ntp-004.aaplimg.com
21758 17.253.84.253 hkhkg1-ntp-002.aaplimg.com
27262 17.253.106.125 dkblp1-ntp-001.aaplimg.com
27390 17.253.106.253 dkblp1-ntp-002.aaplimg.com
27774 17.253.108.125 frcch1-ntp-001.aaplimg.com
27902 17.253.108.253 frcch1-ntp-002.aaplimg.com
28286 17.253.110.125 zaisd1-ntp-001.aaplimg.com
28414 17.253.110.253 zaisd1-ntp-002.aaplimg.com
29310 17.253.114.125 krsel6-ntp-001.aaplimg.com
29438 17.253.114.253 krsel6-ntp-002.aaplimg.com
29822 17.253.116.125 twtpe2-ntp-001.aaplimg.com
29950 17.253.116.253 twtpe2-ntp-002.aaplimg.com
32382 17.253.126.125 usdal4-ntp-001.aaplimg.com
32510 17.253.126.253 usdal4-ntp-002.b.aaplimg.com; usdal4-ntp-002.aaplimg.com

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