RLDP (Ring Light Detection and Protection) of Simplified Optical 3.0 -- Configure Bidirectional Link Detection

4.3.1 Networking requirements
As shown in Figures 4-3, devices A and B are connected by optical fibers. The two lines in the diagram represent the Tx line and Rx line of the optical fiber, and A and B enable the bi-directional link detection function of RLDP. If both the Tx of port A and the Rx of port B, as well as the Rx of port A and the Tx of port B, fail at the same time, the protocol can detect the bi-directional fault and take corresponding actions. If the fault is restored, the administrator can manually restore the protocol status on A and B and restart the detection.
4.3.2 Networking topology diagram

Figure 4-3

4.3.3 Key points for configuration
Enable RLDP globally.

4.3.4 Configure RLDP bidirectional link detection under interface L and specify the handling method when bidirectional faults occur.
Configuration Steps:

# Configure on  DeviceA
.
DeviceA is enabled.
DeviceA# configure terminal
DeviceA(config)# rldp enable
DeviceA(config)# interfaceGigabitEthernet 0/1
DeviceA(config-if-GigabitEthernet0/1)# rldp port bidirection-detect shutdown-port
# Configure on DeviceB.
DeviceB enabled
DeviceB# configure terminal
DeviceB(config)# enable rldp
DeviceB(config)# interfaceGigabitEthernet 0/1
DeviceB(config-if-GigabitEthernet0/1)# rldp port bidirection-detect shutdown-port

4.3.5 Verification configuration result

# Check the RLDP status information of DeviceA
DeviceA> enable
DeviceA# show rldp
rldp state         : enable
rldp hello interval: 3
rldp max hello     : 2
rldp local bridge: 00d0.f822.33aa

-----------------------------------

Interface GigabitEthernet 0/1
port state      : normal
neighbor bridge: 00d0.f800.51b1
neighbor port   : GigabitEthernet 0/1
bidirection detect information:
action: shutdown-port
state: normal
# Check the RLDP status information of DeviceB.
DeviceB enabled
DeviceB# show rldp
rldp state         : enable
rldp hello interval: 3
rldp max hello     : 2
rldp local bridge  : 00d0.f800.51b1

-----------------------------------

Interface GigabitEthernet 0/1
port state: normal
neighbor bridge: 00d0.f822.33aa
neighbor port   : GigabitEthernet 0/1
bidirection detect information:
action: shutdown-port
state: normal

4.3.6 Common Error
(1) The RLDP function is not enabled on either the local or remote end.
(2) The RLDP detection methods configured on the local end and the remote end are inconsistent.
(3) The RLDP negotiation function is not enabled, resulting in a single-ended configuration of RLDP unidirectional link detection that is mistaken for a link failure.