CLI Reference Guide-R05

Chapter 4 | System Management Commands
Synchronous Ethernet
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◆ If SyncE has locked the clock source and the clock source becomes invalid,
SyncE will operate in holdover mode, switching over to the local reference clock
if all available clock source signals fail. If SyncE has never locked the clock
source and no valid clock source exists, SyncE will operate in free-run mode. If
SyncE locked the clock source, SyncE will operate in locked mode.
Note that a clock is said to be in holdover mode if it was previously
synchronized to another clock (normally the primary reference clock) but is
now free-running on its own internal oscillator, whose frequency is being
adjusted using data acquired while it had been synchronized to the other clock.
Example
Console(config)#synce ethernet 1/25 clock-source priority 1
Console(config)#
synce auto-clock-
source-selecting
This command automatically selects the clock source port with the highest priority.
Use the no form to disable automatic clock source selection.
Syntax
[no] synce auto-clock-source-selecting [revertive-switching]
auto-clock-source-selecting - Chooses the clock source port
based on current clock-source port status and priority.
revertive-switching - The active clock source port will be changed
when a clock source port with a higher priority becomes available.
Default Setting
Disabled
Command Mode
Global Configuration
Command Usage
◆ The switch can only be set to automatic clock source selection mode when the
current selection mode is set to manual.
◆ At least one clock source port must be configured before switching to auto
clock source selection mode. All ports configured as clock source port in
manual mode will be kept after changing to auto mode.
◆ If more than one port is configured as clock source port, the port with a valid
clock source signal and the highest priority is selected to be the active clock
source port.
◆ If the configured priorities for two or more clock source ports are the same, it
will choose the smaller numbered port to be the active clock source port.