No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search

Reminder

To have a better experience, please upgrade your IE browser.

upgrade

Configuration Guide - Device Management

S7700 and S9700 V200R013C00

This document describes the configurations of Device Management, including device status query, hardware management, CSS, SVF, PoE, OPS, OIDS, energy-saving management, information center, fault management, NTP, synchronous ethernet, PTP.
Rate and give feedback:
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).
Protection Switching

Protection Switching

The protection switching mechanism of clock synchronization ensures that, if a clock source traced by a switch is missing, another clock source automatically takes over. The new clock source may trace clock signals from the same reference clock as the old clock source or may be a clock source with a lower SSM quality level. When the original clock source is restored, the switch determines whether to re-select a clock source based on the configuration.

Protection Switching in Automatic Clock Source Selection Mode

  • As shown in Figure 13-12, when the network functions normally, the switch determines to trace external clock 1 and its clock tracing path using the automatic clock source selection algorithm based on SSM quality levels and priorities of clock sources.
    NOTE:
    In this chapter, the networking figures use W to represent the westbound interface and E to represent the eastbound interface. W and E indicate the interfaces connecting devices and distinguish the input and output directions of clock signals.
    Figure 13-12  Protection switching in automatic clock source selection mode when a network functions normally
  • As shown in Figure 13-13, if a link fails, the switch determines that the clock source to trace remains unchanged based on the automatic clock source selection algorithm and updates only the clock tracing path.
    Figure 13-13  Protection switching in automatic clock source selection mode in case of a link failure
  • As shown in Figure 13-14, if the clock source is faulty, the switch determines to trace external clock 2 based on the automatic clock source selection algorithm and updates the clock tracing path.
    Figure 13-14  Protection switching in automatic clock source selection mode in case of a clock source fault
  • As shown in Figure 13-15, if the link or clock source fault is rectified, the switch re-traces external clock 1 based on the automatic clock source selection algorithm and updates the clock tracing path.
    Figure 13-15  Protection switching in automatic clock source selection mode when the link or clock source fault is rectified

Protection Switching in Manual Clock Source Selection Mode

  • If the manually specified clock source is normal, the switch traces this clock source.
  • If the manually specified clock source is faulty, the switch works in automatic clock source selection mode, traces a new clock source based on the automatic clock source selection algorithm, and updates the clock tracing path.
  • If the fault affecting the manually specified clock source is rectified, the switch determines whether to trace the recovered clock source based on the automatic clock source selection algorithm.

Protection Switching in Forcible Clock Source Selection Mode

  • If the forcibly specified clock source is normal, the switch traces this clock source.
  • If the forcibly specified clock source is faulty, the switch enters the clock holding state.
  • If the fault affecting the forcibly specified clock source is rectified, the switch re-traces the forcibly specified clock source.
Translation
Download
Updated: 2019-04-20

Document ID: EDOC1100065738

Views: 40186

Downloads: 37

Average rating:
This Document Applies to these Products
Related Version
Related Documents
Share
Previous Next