Configuring Clock Protection Switching Based On Ssm Levels; Establishing The Configuration Task; Configuring The Router To Automatically Select Clock Sources - Huawei netengine80e Configuration Manual

HUAWEI NetEngine80E/40E Router
Configuration Guide - Basic Configurations
9.5 Configuring Clock Protection Switching Based on SSM
Levels
The higher its SSM level, the more accurate a clock is. By default, a clock board uses the most
accurate clock source available.

9.5.1 Establishing the Configuration Task

Applicable Environment
Synchronous Ethernet signals can be used to carry SSM messages. The system then selects one
clock source based on the SSM levels of all the available clock sources. If clock sources are
configured with SSM levels, the configured SSM levels are used; if clock sources are not
configured with SSM levels, the SSM levels carried in the SSM messages are extracted for use.
The SSM levels include Primary Reference Clock (PRC), primary level SSU (SSU-A), second
level SSU (SSU-B), SDH Equipment Clock (SEC), Do Not Use for synchronization (DNU),
and UNK in the descending order. If the SSM level of a clock source is DNU and SSM is enabled,
the clock source is not selected during protection switchover.
The BITS clock has two types of signal. When the BITS clock signal is 2.048 Mbit/s, the clock
board extracts the SSM from the signal. When the BITS clock signal is 2.048 MHz, set the SSM
level manually.
Pre-configuration Tasks
Before configuring protection switchover of clock sources based on SSM levels, complete the
following tasks:
l
Data Preparation
To configure protection switchover of clock sources based on SSM levels, you need SSM levels
of clock sources.

9.5.2 Configuring the Router to Automatically Select Clock Sources

Context
Do as follows on all routers in the clock synchronization network:
Procedure
Step 1 Run:
system-view
The system view is displayed.
Step 2 Run:
clock clear [ 2msync-1 | 2msync-2 ]
Issue 02 (2011-09-10)
Configuring an external clock reference source and its signal type on the device.
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9 Clock Synchronization Configuration
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