Users Guide

Layer 2 Switching Commands 469
ethernet tcn-propagation
Use the ethernet tcn-propagation command to enable topology change
notification from a sub-ring to the major ring. Use the no form of the
command to disable TCN propagation.
Syntax
ethernet tcn-propagation g8032 to g8032
Default Configuration
TCN propagation is disabled by default.
Command Mode
Interface (Ethernet) Configuration mode
User Guidelines
This command enables topology change propagation from sub-ring to a major
ring. If TCN is enabled globally, it is applied to all the instances configured on
the switch. If the global and instance mode configured value is the same, this
command is not shown in the instance mode section in running-config.
Example
This example configures a closed ring node for interface Te1/0/1 and Te1/0/2
using data VLANs 101-103. It assumes that VLANs 100-103 are already
created. A single instance is created and associated with ERP profile1. The
profile sets the hold-off timer to 500 milliseconds. Interface Te1/0/2 is
configured in the Owner role. Interface Te1/0/2 connects to an adjacent
switch port Te1/0/1. Traffic is blocked on these two ports under normal
conditions. VLANs 101-103 are protected. VLAN 100 is used as the
Automatic Protection Switching (APS) VLAN. Only Ethernet CFM messages
at maintenance level 7 are monitored.
console (config)# ethernet ring g8032 ring1
console (config-erp-ring1)#port0 interface te1/0/1
console (config-erp-ring1)#port1 none
console (config-erp-ring1)#open-ring
console (config-erp-ring1)#exit
console (config)#interface Te1/0/2
console (config-if-Te1/0/2)#switchport mode trunk