Enabling MPLS LDP-IGP Synchronization on an Interface

You can enable LDP-IGP synchronization on an interface that belongs to an OSPF or IS-IS process and override global LDP-IGP synchronization.

Perform the following steps.

1. In privileged EXEC mode, enter global configuration mode.
   

   device# configure terminal

2. Enter the configuration mode to an Ethernet port.
   

   device(config)# interface ethernet 0/1

3. Enable IS-IS on an interface.
   

   device(config-if-eth-0/1)# ip router isis

4. Enable LDP-IGP synchronization with IS-IS on the interface.
   

   device(config-if-eth-0/1)# isis ldp-sync enable

5. Configure the OSPF area on the interface.
   

   device(config-if-eth-0/1)# ip ospf area 0.0.0.0

6. Enable LDP-IGP synchronization with OSPF on the interface.
   

   device(config-if-eth-0/1)# ip ospf ldp-sync enable

7. Verify LDP-IGP synchronization with IS-IS on the interface.
   

   device# show isis interface
   Total number of IS-IS Interfaces: 5
   
   Interface: eth 0/1
   Circuit State: UP Circuit Mode: LEVEL-1-2
   Circuit Type: BCAST Passive State: FALSE Circuit Number: 3, MTU: 1500
   Level-1 Auth-mode: None
   Level-2 Auth-mode: None
   Level-1 Metric: 10, Level-1 Priority: 64
   Level-1 Hello Interval: 10 Level-1 Hello Multiplier: 3
   Level-1 Designated IS: R2-03 Level-1 DIS Changes: 
   Level-2 Metric: 10, Level-2 Priority: 64
   Level-2 Hello Interval: 10 Level-2 Hello Multiplier: 3
   Level-2 Designated IS: R2-03 Level-2 DIS Changes: 2
   Next IS-IS LAN Level-1 Hello in 7 seconds 
   Next IS-IS LAN Level-2 Hello in 3 seconds 
   Number of active Level-1 adjacencies: 0
   Number of active Level-2 adjacencies: 0
   Circuit State Changes: 1 Circuit Adjacencies State Changes: 0
   Rejected Adjacencies: 0
   Circuit Authentication L1 failures: 0
   Circuit Authentication L2 failures: 0
   Bad LSPs: 0
   Control Messages Sent: 40 Control Messages Received: 0
   Hello Padding: Enabled
   IP Enabled: TRUE IP Addresses:
      10.30.30.2/28
   IPv6 Enabled: FALSE 
   MPLS TE Enabled: FALSE
   LDP-SYNC: Enabled, State:
   

8. Verify LDP-IGP synchronization with OSPF on the interface.
   

   device# show ip ospf
   OSPF Version Version 2
   Router Id 10.1.1.2
   ASBR Status No
   ABR Status No (0)
   Redistribute Ext Routes from
   Initial SPF schedule delay 0 (msecs)
   Minimum hold time for SPFs 0 (msecs)
   Maximum hold time for SPFs 0 (msecs)
   External LSA Counter 0
   External LSA Checksum Sum 00000000
   Originate New LSA Counter 9
   Rx New LSA Counter 6
   External LSA Limit 174762
   Database Overflow Interval 0
   Database Overflow State : NOT OVERFLOWED
   RFC 1583 Compatibility : Enabled
   Slow neighbor Flap-Action : Disabled, timer 300
   Nonstop Routing: Disabled
   Graceful Restart: Disabled, timer 120
   Graceful Restart Helper: Enabled
   LDP-SYNC: Globally enabled, Hold-down time 66 sec
   Interfaces with LDP-SYNC enabled:
   eth 0/1 

Example

The following example shows the previous steps.

device# configure terminal
device(config)# interface e 0/1
device(config-if-eth-0/1)# ip router isis
device(config-if-eth-0/1)# isis ldp-sync enable
device(config-if-eth-0/1)# ip ospf area 0.0.0.0
device(config-if-eth-0/1)# ip ospf ldp-sync enable