Troubleshooting

If you are having difficulty using Laureline, the following may be of some use. Don’t hesitate to contact us with questions.

Bottom status LED stays solid red

The GPS is not tracking satellites and is thus not outputting a pulse-per-second signal. Check that the antenna is firmly connected, that it is compatible with the 5V power Laureline supplies, and that it has a clear view of the sky.

Bottom status LED flashes green but top LED is orange and NTP does not respond

The GPS is not sending valid UTC time-of-day data. Before it can do so it must receive a complete almanac from the GPS satellites. This process can take up to 30 minutes.

NTP reports “stratum 16”, “Server dropped: no data”, or “no server suitable for synchronization found”

The GPS receiver has lost satellite lock and is not outputting a pulse-per-second signal. Check that the antenna connection is secure and that it has a clear view of the sky.

Status LEDs and Ethernet LEDs do not illuminate or are dim

Disconnect the GPS antenna and see if the problem persists. If it is resolved then your antenna is drawing too much power. If it is not due to a fault then you may need to use a DC block and external power source.

If you have recently flashed a firmware upgrade, the firmware may be corrupt. Try re-downloading the firmware.

Known Issues

Leap seconds

Laureline does not currently set the leap second bit in NTP replies. This is because the Laureline software itself does not support leap seconds. However, the GPS receiver does. When a leap second occurs Laureline will immediately step its own internal clock in response to the time-of-day data from the GPS and continue serving the correct time. But because the leap bit was not set in any NTP replies, clients that do not receive NTP from any other time source will not step in unison and will be “left behind”. Manual intervention will be required e.g. by running ntpdate to step the clock, because ntpd will reject any time source that has a large offset.

If any other NTP servers are in use that set the leap bit, or if leap second data is manually loaded into the client, then the client will step in unison and continue operating correctly. SNTP clients such as routers and switches are typically not affected as they simply periodically set their local clock to whatever the server replies. Their clock will be off by one second until the next check, then will be correct.