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
BSDCan - BSDCan

BSDCan is a technical BSD conference held in Ottawa, Ontario, Canada.

BSDCan

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.

Anyone else getting these warnings when running #OpenNTPD on either #FreeBSD or #HardenedBSD ?

$ sudo service openntpd start
Performing sanity check on openntpd configuration:
configuration OK
Starting openntpd.
creating new /var/db/ntpd.drift
constraint: failed to load constraint ca
constraint: failed to load constraint ca
constraint: failed to load constraint ca
constraint: failed to load constraint ca

I don't really know what that failure is or what it means. I don't know if I should take action--or even what kind of action to take.

Today's cool activity. Preparing and network booting a stack of Lenovo M920q Tiny ThinkCentre with #OpenBSD and perform unattended installs ready for #ansible bootstrapping. These will be spread around the network as Stratum 3 time servers for various devices to sync off #OpenNTPD
OpenBSD

the main OpenBSD page

My joyful #journey with #openbsd 🐡thickens.
Today I boosted my #selfhosting #services with #nfs, teaming up with #adblock, #caldav, #carddav, #cgit, #httpd, #vnstat, #openntpd

with my #MIDI to WiFi "port" I seem to have accidentally fixed a bug in #OpenNTPd
tbh likely only in the linux port, not in the #OpenBSD original.

meanwhile it's #fantasound (stereo+1=3)

https://github.com/openntpd-portable/openntpd-portable/issues/76

openntpd keeps terminating with a `ntp: recvfrom: Permission denied` · Issue #76 · openntpd-portable/openntpd-portable

for some reasons I need a precise time on my computer recently. so I started to investigate why openntpd wasn't running. for a while I just started it when I needed it, but now I noticed it stops r...

GitHub
Would you like #OpenNTPD re-imported into #HardenedBSD base?
Yes
93.8%
No
6.3%
Poll ended at .
My Strarum 1 time server is back to observing its usual 28 satellites after the recent solar event. Accuracy should be back to normal now #NTP #Time #OpenNTPD #OpenBSD