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Configuring a PTP Clock Source

Context

To implement clock synchronization on a switch, configure a clock source first. If a switch uses PTP messages to restore clock signals (for example, an upstream device uses 1588v2 to transmit clock signals), configure the switch to trace a PTP clock source.

When multiple clock sources are available, a switch selects a clock source as its reference clock according to the clock source priority and Synchronization Status Message (SSM) quality level.
  • Clock source priority

    The default priority for a clock source is 0, indicating that this clock source does not participate in clock source selection. To enable the clock source to participate in clock source selection, specify a priority for it.

    A lower priority value indicates a higher priority of a clock source.

  • Clock source SSM quality level

    An SSM is a group of codes used to indicate the clock quality level on a synchronized network. SSM reflects the level of synchronous timing signals transmitted on a synchronous timing link. A higher clock accuracy indicates a higher SSM quality level. A device can be configured to select a clock source according to the SSM quality level.

    SSM quality levels are sorted in descending order of preference: primary reference clock (PRC), Synchronization Supply Unit A (SSU-A), Synchronization Supply Unit B (SSU-B), SDH equipment clock (SEC), and Do Not Use (DNU).

Procedure

  1. Run system-view

    The system view is displayed.

  2. Run clock ethernet-synchronization enable

    The synchronous Ethernet function is enabled.

    By default, the synchronous Ethernet function is not enabled.

  3. Run clock source ptp synchronization enable slot slot-id

    The clock synchronization function is enabled for the PTP clock source.

    By default, the clock synchronization function is not enabled for a PTP clock source.

  4. Run clock source ptp priority priority-value slot slot-id

    A priority is configured for the PTP clock source.

    The default priority of a PTP clock source is 0.

  5. Run clock source ptp ssm { unk | prc | ssua | ssub | sec | dnu } slot slot-id

    An SSM quality level is configured for the PTP clock source.

    By default, the SSM quality level of a PTP clock source is unknown.

Copyright © Huawei Technologies Co., Ltd.
Copyright © Huawei Technologies Co., Ltd.
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