How often will NTP update the time? ** solved **

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cbhiii
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How often will NTP update the time? ** solved **

Post by cbhiii »

How often does NTP update the Meteohub clock? After a reboot the NTP log will contain nothing for a period of many days. It only seems to set the time after a reboot.
Station: Davis Vantage Pro2 Plus
Hardware: Raspberry Pi 2 (Meteohub status)
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admin
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Re:How often will NTP update the time?

Post by admin »

yes, ntp seems to be quite silent. However clock is well in sync and the ntp daemon is running.
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Re:How often will NTP update the time?

Post by mvpel »

The \"synchronized to...\" message means that the NTP service has gotten enough accurate data from that server to be able to consider it a reliable time source.

Once that happens, the NTP daemon will send a packet once every 64 seconds for a while, then back down to one packet every 128, 256, 512, and 1024 seconds (17.1 minutes) as it confirms that the local clock and the remote time server are stable and reliable. None of that activity is logged, as it would be a waste of log space.

The only log event you'd see between reboots is if the time server to which the NTP service is synchronized became unavailable or started sending inaccurate time data.

A good choice for NTP servers is to use the NTP Pool system - I'd suggest this be used as the default config in the new install images. My NTP server list is 0.us.pool.ntp.org and 1.us.pool.ntp.org.

The europe.pool.ntp.org zone has 894 active servers available.
cbhiii
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Re:How often will NTP update the time?

Post by cbhiii »

Great information and explaination. Now it makes sense.

I'll be sure to check out the NTP Pool Project as well.

Thanks!
Station: Davis Vantage Pro2 Plus
Hardware: Raspberry Pi 2 (Meteohub status)
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