CLI Reference Guide-R05

Chapter 4 | System Management Commands
Synchronous Ethernet
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◆ If SyncE has been enabled on more than one port, the switch will choose the
clock source port based on the current clock source port status and priority.
◆ A port can be forced to be the clock source port regardless of the clock’s signal
status.
Example
Console(config)#sync ethernet 1/12 clock-source priority 1
Console(config)#
synce ssm ethernet This command configures a port to receive/send Synchronization Status Messages
(SSM), and sets the priority used for this port in clock source port selection. Use the
no form to stop using clock selection based on SSM.
Syntax
synce ssm ethernet unit/port [priority priority]
no synce ssm [ethernet unit/port]
unit - Unit identifier. (Range: 1)
port - Port number. (Range: 1-12)
priority - The priority used for clock source selection.
(Range: 1-65535)
Default Setting
Disabled
Command Mode
Global Configuration
Command Usage
General Information
◆ SSM provides a mechanism for downstream SyncE devices to synchronize with
the Primary Reference Clock or the highest quality clock available. If an
upstream network failure breaks this link, the synchronization function can
take appropriate action based on SSM and pre-set priorities to select an
alternate source of synchronization.
◆ This command only enables a port to send/receive SSM. It does not designate a
specific port to be used as the clock source port. Use the synce clk-src-ssm
command to configure the clock source.
◆ Only SSM will be extracted from the Ethernet Synchronization Message
Channel (ESMC). No other information from the ESMC will be forwarded. SSM
will be sent out of the specified port indicating the clock source selected by
SSM or the manually configured clock source.