17-15
Ethernet Card Software Feature and Configuration Guide, R7.2
January 2009
Chapter 17 Configuring Cisco Proprietary Resilient Packet Ring
Creating the Bridge Group and Assigning the E thernet and SPR Interfaces
Creating the Bridge Group and Assigning the Ethernet and SPR Interfaces
The default behavior of the ML-Series cards is that no traffic is bridged over the Cisco proprietary RPR
even with the interfaces enabled. This is in contrast to many Layer 2 switches, including the
Cisco Catalyst 6500 and the Cisco Catalyst 7600, which forward VLAN 1 by default. The ML-Series
card will not forward any traffic by default, including untagged or VLAN 1 tagged packets.
For any Cisco proprietary RPR traffic to be bridged on an ML-Series card, a bridge group needs to be
created for that traffic. Bridge groups maintain the bridging and forwarding between the interfaces on
the ML-Series card and are locally significant. Interfaces not participating in a bridge group cannot
forward bridged traffic.
To create a bridge group for Cisco proprietary RPR, you determine which Ethernet interfaces need to be
in the same bridge group, create the bridge group, and associate these interfaces with th e bridge group.
Then associate the SPR interface with the same bridge group to provide transport across the
Cisco proprietary RPR infrastructure.
Figure 17-8 illustrates a bridge group spanning the ML-Series card interfaces, including the SPR virtual
interface of Cisco proprietary RPR.
Step 7 Router(config-if)# interface pos 1 Enters the interface configuration mode to configure the
second POS interface that you want to assign to the SPR.
Step 8 Router(config-if)# encapsulation lex Sets POS interface encapsulation as LEX (default).
Cisco proprietary RPR on the ML-Series card requires
LEX encapsulation.
Step 9 Router(config-if)# spr-intf-id
shared-packet-ring-number
Assigns the POS interface to the SPR interface. The
shared packet ring number must be 1 (the same shared
packet ring number that you assigned in Step 3), which is
the only shared packet ring number that you can assign
to the SPR interface.
Step 10 Router(config-if)# carrier-delay msec
milliseconds
(Optional) Sets the carrier delay time. The default setting
is 200 milliseconds, which is optimum for SONET/SDH
protected circuits.
Step 11 Router(config-if)# pos trigger defect
ber_sd-b3
(Optional) Configures a trigger to bring down the POS
interface when the SONET/SDH bit error rate exceeds
the threshold set for the signal degrade alarm. Bringing
the POS interface down initiates the wrap.
This command is recommended for all Cisco proprietary
RPR POS interfaces since excessive SONET/SDH bit
errors can cause packet loss.
Step 12 Router(config-if)# no shutdown Enables the POS port.
Step 13 Router(config-if)# end Exits to privileged EXEC mode.
Step 14 Router# copy running-config
startup-config
(Optional) Saves the configuration changes to NVRAM.
Command Purpose