How to ensure the Operating System and Hardware clocks are in sync.


How to ensure the Operating System and Hardware clocks are in sync using the HTML5 /ui/ and the SSH Command Line using hwclock


  • How to we get the Unitrends appliance to show the correct time?
  • You have a need to change or set the system time.
  • You find a discrepancy between the hardware BIOS time and the Operating System time.
  • You see a message in /var/log/messages or dmesg logs stating 'clock skew too great'.


First, verify that the RecoveryOS clock settings are correct.

Using the HTML5 /ui/ Web Administrative Interface:

  1. Click on the CONFIGURE page, from the Appliances tab above, select the name of the Unitrends appliance.
  2. Click the Edit button above, then click on the  Date Time tab.
  3. Ensure the radial button next to "Enter a date and time for your appliance." is selected, and update Date, Time, and Timezone as needed and then click Save.

Now let's verify that your Hardware BIOS clock and the OS clock are the close in time. Use an SSH terminal application (e.g.: PuTTY) to connect to the Unitrends appliance. Execute this command to find out the OS and Hardware time:

How much is the time difference? Is the first entry the correct time, but the bottom entry off? You can get the hardware clock to show the time as in system clock by executing the following command:
hwclock --systohc

Now, run the command that compares the system and hardware clocks again to check that the two are in close sync:

At this point, the two should be closely in sync. If you which to change the UI to use NTP Servers for syncing the time, you can go back to the first steps provided and click on "Use an NTP Server."


You should be on the new Unitrends web HTML5 interface. If for some reason you are on the Legacy /recoveryconsole/ use this step below to substitute the steps in the HTML5 /ui/.

  1. In the Legacy Interface, go to Settings > Systems, Updates and Licensing > Date/Time, and you can change the time there.

Have more questions?

Contact us

Was this article helpful?
0 out of 0 found this helpful

Provide feedback for the Documentation team!

Browse this section