Example For Selecting The Clock Source Based On The Ssm Quality Level - Huawei Quidway S9300 Configuration Manual

Quidway S9300 Terabit Routing Switch
Configuration Guide - Device Management
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11.8.2 Example for Selecting the Clock Source Based on the SSM
Quality Level
Networking Requirements
On a ring network, the clock of a Switch is configured as the primary reference clock. You can
set the priorities of clock sources so that so that the clock source is selected based on the SSM
quality level. Timing loops must be prevented.
As shown in
reference clock. In this example, the primary reference clock on the ring network is generated
by the local oscillator. In actual networking, the primary reference clock may be obtained from
the BITS interface of Switch A. The Switches obtain clock signals from the LPUs and select the
clock source based on the SSM quality level. The normal clock syntonization direction is shown
by the red arrows. If the clock signal fails to be transmitted in this direction, the Switches can
quickly change the clock syntonization direction, as shown by the blue arrows.
Figure 11-2 Networking diagram of clock syntonization
BITS
Issue 03 (2011-12-29)
#
interface GigabitEthernet5/0/7
clock right-frame 10
#
Configuration file of Switch C
#
sysname SwitchC
#
clock priority 5 source 5 system
#
interface GigabitEthernet2/0/0
clock left-frame 40
#
interface GigabitEthernet2/0/3
clock left-frame 30
#
Figure 11-2, three S9306s form a ring network. The clock of Switch A is the primary
SwitchA
GE 2/0/0
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11 Ethernet Clock Syntonization Configuration
GE 2/0/0
SwitchB
Normal clock synchronization
direction
Clock synchronization direction after signal
transmission between SwitchA and SwitchB fails.
SwitchC
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