ntpsec.anastrophe.com

Attention:
This service is shut down for general clock sync. I will still accept peering requests, but service may be down at times. I am no longer running dual timeservers on battery backup; I can no longer offer four-nines availability (so sad).

• NTP and SNTP service is available on port 123.
  
• NTS service is no longer available. Comcast/Xfinity blocks UDP port 123 packets with a payload larger than 48 bytes, therefore, NTS will not work.
  
• This server is part of the NTP Pool Project (North America, US pool)
• ntpviz generator (this website):
  • Raspberry Pi 4 Model B Rev 1.5, 4gb ram
  • OS: Raspbian 11.x - Bullseye
  • Webserver: NGINX
  • Monitoring: Monit (highly recommended)
  • Roughly 5 minutes once per hour to generate all graphs
• A portion of the journey here: A Brief History of Time. Sorta.(outdated), and a more recent configuration (currently only one timeserver).
• ADS-B - Flight Tracking For Fun And No Profit
• Most of the time, only one of a-ntpsec or b-ntpsec will be 'up' I swap one or the other in place if significant downtime is necessary for maintenance.

a-ntpsec.anastrophe.com

• Refclock: uBlox Neo m8t HAT on a Raspberry Pi 3 Model B+ Rev 1.3
• OS: Raspbian 11.x - Bullseye (64bit)
• Time sync: gpsd 3.25 and NTPsec ntpsec-1.2.3
1 hour graphs
3 hour graphs
6 hour graphs
12 hour graphs
24 hour graphs
72 hour graphs
7 day graphs

b-ntpsec.anastrophe.com

• Refclock: Adafruit Ultimate GPS HAT on a Raspberry Pi 3 Model B+ Rev 1.3
• OS: Raspbian 11.x - Bullseye (64bit)
• Time sync: gpsd 3.25 and NTPsec 1.2.2a
1 hour graphs
3 hour graphs
6 hour graphs
12 hour graphs
24 hour graphs
72 hour graphs
7 day graphs

All graphs generated with ntpviz.

Many (most?) elements shamelessly cadged from Royce Williams' most excellent NTP resource site.

This site tests "A+" on the Qualys SSL Labs Server Test page.