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• Load the kernel module ptp_kvm, either automatically at boot or manually.
  This will create a ptp device in /dev/. To determine which device is the one created by ptp_kvm, simply check that the file /sys/class/ptp/ptp*/clock_name does indeed say "KVM virtual PTP". 
  In this example, our ptp_kvm device is ptp0.

• Synchronize the system clock with the PTP clock.

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