#openntpd — Public Fediverse posts

Worried about time? BSDCan early registration ends April 30th! Worried about network time? Henning Brauer is giving the talk: OpenNTPD - 20 years and a few milliseconds later at BSDCan 2026:

OpenNTPD hit the OpenBSD CVS in late 2004. Now, 20 years and a few milliseconds later, it's time to look back, how it was received, and what changed.

We'll briefly look at the world 20 years wrt having systems' clocks synchronized (or not), the design of OpenNTPD and how it fundamentally differed from everything around back then, and how it was - intentionally or not - misunderstood by some with very little knowledge but a lot of opinion, and how FUD from 20 years ago is still around. We'll cover what changed in OpenNTPD after it went public, and what changed in OpenBSD to increase accuracy substantially. We'll also cover the later added constraint feature to further defend against getting fed incorrect time.

#OpenNTPD #bsdcan #openbsd #cvs #time

BSDCan https://www.bsdcan.org/2026/ Talk Friday 2026-06-19: 13:15 - 14:05 DMS 1130
OpenNTPD - 20 years and a few milliseconds later
Henning Brauer
https://www.bsdcan.org/2026/timetable/timetable-OpenNTPD---20.html
To register https://www.bsdcan.org/2026/registration.html @bsdcan #openbsd #openntpd #ntp #freebsd

Needed an #NTP server on a Raspberry Pi. To keep it light, I chose #OpenNTPD.

Not a great idea.

If your clock is off by more than 180 seconds, it won't adjust it; logs say

adjtime failed: Invalid argument

Now, according to the man page, it will jump to adjust larger offsets on startup, but apparently #Debian has patched this to require adding `-s` to /etc/default/openntpd.

They also don't support `constraint from` config stanzas used to get a trusted date via HTTPS.

Trying #chrony now.

#OpenBSD 7.7 has been released (#BSD / #NetBSD / #386BSD / #Unix / #LibreSSL / #OpenSSH / #OpenBGPD / #OpenSMTPD / #OpenNTPD / #OpenIKED / #rpkiClient / #mandoc) https://openbsd.org/

#chronyd and #openntpd only step time in the first couple seconds after startup. During this time my internet access is not yet fully functional.

#OpenBSD 7.5 has been released (#BSD / #NetBSD / #386BSD / #Unix / #LibreSSL / #OpenSSH / #OpenBGPD / #OpenSMTPD / #OpenNTPD / #OpenIKED / #rpkiClient / #mandoc) https://openbsd.org/

Please donate to The OpenBSD Foundation to help them reach their goal for 2022.

They do not only provide support for #OpenBSD, but also to related projects such as #OpenSSH, #OpenBGPD, #OpenNTPD, #OpenSMTPD, #LibreSSL, #mandoc and #rpki-client.

Thank you! :flan_thumbs:​

https://www.openbsdfoundation.org/

Depuis une mise à jour d'#ArchLinux, #OpenNTPD (de OpenBSD) ne synchronise plus l'horloge. Retour au traditionnel #ntpd, qui marche. (Et qui permet de restreindre les accès par adresse IP.)

#NTP #sysAdmin