The phc_ctl utility is part of Linux PTP. If linuxptp is installed on the server, phc_ctl can be used to set the adapter clock and compare the time offset against the system clock.
Get System Clock Time
# phc_ctl CLOCK_REALTIME getGet NIC Clock Time
# phc_ctl <interface> getCompare System and NIC Clocks
# phc_ctl /dev/ptpN cmpSet NIC Clock from System Clock
# phc_ctl /dev/ptpN setThe NIC clock can be specified by the sfptpd interface or by device number.