6-4
Cisco ME 3800X and 3600X Switch Software Configuration Guide
OL-23400-01
Chapter 6 Configuring Synchronous Ethernet
Understanding SyncE
Figure 6-2
Broken Network Link
Figure 6-3
shows how the REP segment handles the broken link to avoid timing loops in the SyncE
network.
Figure 6-3
SyncE REP Segment
When you configure the SyncE REP workaround, you can configure these SyncE features:
•
Hold-off timeout—If a clock source goes down, the switch holds the fail signal for a specific time
period before removing the source and restarting the synchronization process. Configure the
hold-off timeout by entering the network-clock-select hold-off timeout global configuration
command.
•
Wait-to-restore timeout—If a failed SyncE source comes up, the switch waits for a specific time
period of time before considering the source as available in the selection process. The default time
is 300 seconds. Configure wait-to-restore timeout by entering the network-clock-select
wait-to-restore global configuration command.
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