8

The Problem I have 4 Raspberry Pis running on my local network. All 4 Raspberry Pis are posting messages every 5 seconds to an Azure IoT hub.

The problem is that when time drifts off, I'm getting authentication errors from the IoT hub and then my app crashes.

I have noticed that when connected via a network cable there is no issue. But errors are much more common on WiFi. Using WiFi is the desired use case.

I have also observed that power cycling will not trigger Windows IoT to update the time, but a restart will.

My current strategy I want to trigger the same time update mechanism that happens on a restart but in a controlled manner. I'm currently attempting to have a power-shell script run every hour to resync.

Where I need help I'm trying to run the command w32tm /resync /force but when I do I get the following error. Sending resync command to local computer The computer did not resync because no time data was available.

I have no idea why. This makes be think that maybe Windows IoT is using something else to get the current time. I really have not clue.

Any suggestion would be greatly appreciated.

Improve this question

2 Answers 2

Reset to default
1

The Windows IoT hub only requires 2-second resolution to prevent auth errors. Rather than forcing a resync every hour, you just need to configure the w32tm to use the same NTP servers as your RPis:

w32tm /config /manualpeerlist:"0.pool.ntp.org 1.pool.ntp.org 2.pool.ntp.org" /syncfromflags:manual /reliable:yes /update

Note the removal of time.windows.com. It is critical here to pass the /update flag otherwise the change will not be activated. From the w32tm docs:

Changes to configuration are not used by Windows Time unless the service is restarted or the /update switch is used.

Improve this answer
0

Those darn error messages. Instead of saying that there are no servers in the list to connect to - it generically returns no time data was found :D

Try this command with your resync/force flags

w32tm /config /syncfromflags:manual /manualpeerlist:"0.windows.time.com 1.pool.ntp.org" /resync /force

On startup there must be something similar supplying NTP servers.

You can use any time server you like even a local NTP server if you can set one up.

Improve this answer

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.