In this section
When PTP time synchronization is configured using the ntservice.ini file as described in this section, the configuration is saved in non-volatile memory. Therefore this is the recommended way to configure PTP time synchronization.
However, the PTP clock on the SmartNIC can also be managed using the PTP management interface defined by the IEEE 1588-2008 specification. This interface can be used to monitor the state and status of the PTP clock. It also enables configuration of vital PTP clock parameters at runtime. The interface is fully supported. However these changes cannot be stored to a non-volatile memory. So, if this PTP management interface is used, the configuration must be set up again after each reboot of the driver.
Configuration options using the ntservice.ini file
The NT SmartNICs implement PTP version 2 and offer a variety of configuration options. They implement the time-of-day synchronization method defined in the protocol. This also ensures phase synchronization and frequency synchronization. Thus the frequency-synchronization-only mode of the PTP protocol cannot be selected. The PTP implementation of the SmartNICs can only use a PTP clock type Ordinary Clock. Therefore the SmartNIC cannot act as a boundary clock or as a transparent clock.
Using PTP as time reference
To use PTP as time reference, just add PTP in the list of clock references (see Configuring the Time Synchronization Connectors and the Time Synchronization Time and Frequency Reference Priorities), and the SmartNIC tries to find a PTP grandmaster clock to synchronize against, using the PTP Ethernet port on the SmartNIC.