Capture Card Clock Differs from System Clock

Document ID : KB000048300
Last Modified Date : 14/02/2018
Show Technical Document Details


I see the following message on the System Status page, in the Capture Card Physical Port Status section:

"Capture card clock differs from system clock by N seconds."


The capture card has an independent clock that stamps the time of incoming packets. In normal operation, this clock is synchronized with the Multi-Port Monitor system clock. The error message appears when there is a discrepancy between the Multi-Port Monitor system clock and the clock on the capture card. The discrepancy can occur when, for example, someone manually changes the time of the system clock.

Synchronize the clocks using the following methods:

  • Immediately synchronize the clocks. Run the following command from the Linux command-line interface on the appliance. This command stops the nqcapd and nqmetricd processes, which disrupts monitoring. The processes are restarted after the clocks are synchronized.

    sudo /opt/NetQoS/scripts/syncNapatechClock --force

  • Maintain synchronization. Run the Network Time Protocol (NTP) to maintain synchronization between the clocks. You can configure NTP with the Network Settings Utility on the appliance. To open the utility, run the following command from the Linux command-line interface:

    sudo /opt/NetQoS/tui/tui-setup.php

In the utility, type the host name or IP address of your NTP server in the NTP Server field. The default is