KB88916
Published: May 5, 2020
Revision: 2.0

System Time may be incorrect after reboot


Applies To:

Firmware for GRV-EPIC-PR1

Versions Affected:

All versions to .1.5.0

Resolved In Version:

2.0.0


Symptoms:

With the following conditions, when you manually set the time zone and time (from groov Manage Home, click System >  Time, then select a Region and Locality, then manually enter hours, minutes, and seconds), a subsequent reboot sets the System Time incorrectly.

  • NTP is not configured, or
  • NTP cannot access the time servers (no internet access)
The following list explains the time differences you may observe:
  • If the Region and Locality you select is positively offset from UTC, after a reboot, the System Time will be set to the time the reboot was performed plus the offset. For example, for Asia (Region) and Hong_Kong (Locality), the offset from UTC is +7. If you set the hours, minutes, and seconds to 8:00:00 AM, and then you reboot at 1:00:00 PM, the System Time will be set to 8:00:00 PM (1:00:00 PM plus the 7 hours offset).
  • If the Region and Locality you select is negatively offset from UTC, after a reboot, the System Time will be set incorrectly as follows:
    • If the time zone in the Region and Locality is offset from UTC by a quantity smaller than the difference between the time you last set in groov Manage and the time you rebooted, then the System Time will be set to the time the reboot was performed minus the offset. For example, for America (Region) and Los_Angeles (Locality), the offset is -8 (quantity is 8). If the last set time was 10:00:00 AM and you reboot at 9:00:00 PM, the difference between those two times is 11. Because the offset (8) is smaller than the difference (11), after the reboot, the System Time will be set to 1:00:00 PM (9:00:00 PM minus the 8 hours offset).
    • If the time zone in the Region and Locality is offset from UTC by a quantity larger than the the difference between the time you last set in groov Manage and the time you rebooted, then the System Time will set to the time you last set in groov Manage. For example, for America (Region) and Los_Angeles (Locality), the offset from UTC is -8 (quantity is 8). If the last set time was 10:00:00 AM and you reboot at 1:00:00 PM, the difference between those two times is 3. Because the offset (8) is larger than the difference (3), after the reboot, the System Time will be set to the time you last set in groov Manage: 10:00:00 AM.

Workaround:

Do the following:

  • If the GRV-EPIC-PR1 has internet access, then enable and configure NTP. From the groov Manage Home page, click System > Time. Click Enable NTP, then Set NTP.
  • If you cannot enable NTP or the GRV-EPIC-PR1 does not have access to the internet, then:
    1. From the groov Manage Home page, click System > Time.
    2. Set the Time Zone to UTC by selecting Universal for Region. Click Set Zone.
    3. Set the Time to the current time for UTC. Make sure the date and time are correct. Click Set Time.
    4. Set the Time Zone to your desired geographic location. Click Set Zone.

Resolution:

Opto 22 has resolved this issue.

Questions?

Contact: Opto 22 Product Support.
Phone: 800-835-6786 or 951-695-3080
Email: support@opto22.com


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