CLI Reference Guide-R05

Chapter 4 | System Management Commands
Synchronous Ethernet
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synce This command enables SyncE on all ports that support SyncE. Use the no form to
disable SyncE on all ports that support SyncE.
Syntax
[no] synce
Default Setting
Disabled
Command Mode
Global Configuration
Command Usage
◆ This command enables SyncE on ports 25-28. It does not configure any of these
port to be the clock source.
◆ SyncE must be enabled on a port before the clock selection method can be set.
Selection options include manual (synce ethernet clock-source), automatic
(synce auto-clock-source-selecting), or forced (synce force-clock-source-
selecting).
◆ SyncE frequency synchronization uses physical layer Ethernet to distribute
timing information. A synchronization chain is formed by using a stratum 1
traceable source at one end which is then recovered at downstream PHYs and
retransmitted down the chain. Every node in the chain must be capable of
recovering and re-transmitting frequency synchronization signals.
◆ SyncE provides timing synchronization through the physical layer, while PTP
(Precision Time Protocol) uses a higher level packet protocol which can result in
Table 25: Sync-E Commands
Command Function Mode
synce Enables SyncE on all ports that support SyncE GC
synce ethernet Enables SyncE on a port that supports SyncE GC
synce ethernet clock-source Manually sets a port as a clock source or candidate clock
source at the specified priority
GC
synce auto-clock-source-
selecting
Automatically selects the clock-source port with the
highest priority
GC
synce force-clock-source-
selecting
Sets the local clock as the active clock source, or sets a port
to be the active clock source
GC
synce ssm ethernet Configures a port to receive/send SSM messages, and sets
the priority used for this port in clock source port selection
GC
synce clk-src-ssm Uses SSM to select the clock source according to the SSM
quality level, priority and port number
GC
show synce Shows SyncE status, selection mode, clock source status,
and SSM status
PE