LDP LSRs set up LSPs using OSPF. When an LDP session fault (non-link fault) occurs on the primary LSP or the primary LSP recovers from a fault, synchronization between LDP and OSPF can prevent traffic loss caused by switchovers of the primary and backup LSPs.
The following uses the configuration of Core_SPE1 on the core ring as an example. The configurations of Core_SPE2 and Core_SPE3 are similar to the configuration of Core_SPE1, and are not mentioned here.
interface Eth-Trunk4 ospf ldp-sync //Enable synchronization between LDP and OSPF on the protected interface. ospf timer ldp-sync hold-down 20 //Set a Hold-down time that an interface uses to delay setting up an OSPF neighbor relationship until an LDP session is set up. # interface Eth-Trunk5 ospf ldp-sync ospf timer ldp-sync hold-down 20 # interface Eth-Trunk17 ospf ldp-sync ospf timer ldp-sync hold-down 20 # interface XGigabitEthernet6/0/4 ospf ldp-sync ospf timer ldp-sync hold-down 20 #
The following uses the configuration of Site1_UPE1 as an example. The configurations of Site1_UPE2, Site2_UPE3, Site2_UPE4, Site3_UPE5, and Site3_UPE6 are similar to the configuration of Site1_UPE1, and are not mentioned here.
interface Eth-Trunk7 ospf ldp-sync ospf timer ldp-sync hold-down 20 # interface Eth-Trunk17 ospf ldp-sync ospf timer ldp-sync hold-down 20 #