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Clock Offset Consensus

Watch several NTP sources form offset intervals, isolate a bad peer, and slew the local clock toward consensus.

Correction to apply to the local clock0 ms means no correction, +2.38 ms means the local machine is that much slow and needs to be slewed forward.0.000.571.131.702.272.833.40GNSS PPS grandmasterroof antenna · narrow interval, hardware PPS edge2.38 msPTB Berlin stratum 1Berlin · tight WAN sample, low jitter2.37 msUTC(OP) peerParis · Observatoire de Paris backed source2.39 msFrankfurt stratum 2Frankfurt · clean enough, wider network uncertainty2.40 msAsymmetric WAN peerfar edge · bad reverse path, offset bias1.15 msLocal correction estimate0.00 ms
Step 1 / 7Local drift appears

Start with the failure mode. Your local oscillator drifts on its own, so even a quiet server can be milliseconds wrong after only a couple of minutes.

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