Time Sync (WAN)¶
Accurate time synchronization is critical for WAN teleoperation. When operating over the internet, each edge computer must have its system time calibrated.
1) Install and start Chrony¶
sudo apt install chrony -y
systemctl status chrony # should show "active (running)"
2) Check sync accuracy¶
chronyc tracking | grep 'System time\|RMS offset'
| Metric | Good (ms) | Acceptable (ms) | Poor (ms) |
|---|---|---|---|
| System time | < 1 | 1 - 10 | > 10 |
| RMS offset | < 5 | 5 - 20 | > 20 |
3) Force immediate sync (if needed)¶
sudo chronyc burst 4/4
sudo chronyc makestep
After network changes (e.g., Wi-Fi → Ethernet), restart:
sudo systemctl restart chronyd
sleep 5
sudo chronyc makestep
Learn more: chrony