Enabling PTP support for capture adapters
The capture adapters for LiveWire support the Precision Time Protocol (PTP). This protocol allows the adapters to sync to a time source on the network that may be more accurate than the clock on LiveWire. If you have multiple capture adapters, you can sync the adapters to a single clock source, as well as allow the packets received on the adapters to have more accurate timestamps. See also Synchronizing the capture engine clock.
To enable PTP support for the adapters, you must manually edit a config file and restart some services on the Capture Engine. The instructions for enabling PTP support on the Capture Engine are provided below.
To enable PTP support on the Capture Engine:
1. SSH into the Capture Engine.
2. Stop the Capture Engine service.
◦ service omnid stop
3. Open the file /etc/omni/ntservice.ini
◦ This file uses the INI format.
◦ The file is broken up into sections. Each section has a name wrapped in  (e.g [Adapter0]), all of the fields below the section name apply to that section.
4. Find the adapter section corresponding to the adapter you wish to configure. Make note of the section name.
◦ Adapter sections have section names which follow the format [AdapterN] where N is a number starting at 0 and incremented by one for each Napatech adapter present on the system.
5. Close the /etc/omni/ntservice.ini file.
6. Open the file /etc/omni/ntoverrides.ini
◦ This file has the same format as the /etc/omni/ntservice.ini file.
◦ This file is used to override the default settings of configuration parameters in the /etc/omni/ntservice.ini file.
7. Add the section name of the adapter retrieved in the /etc/omni/ntservice.ini file.
8. Below this section, add the necessary PTP configuration parameters.
◦ If more than one card is being configured, add the next section name and the necessary PTP configuration parameters.
9. When all of the adapters have been configured, save and close the file.
10. Run the ntcard_setup script to update the configuration file with the PTP settings.
◦ service ntcard_setup start
◦ This script may take a couple of minutes to complete.
11. Once the script is finished, restart the Capture Engine service.
◦ service omnid start