Mandatory

  • Enable CEF switching
  • Configure LDP on every label-enabled interface

Optional

  • Configure MPLS ID
  • Configure MTU size for labelled packets
  • Configure IP TTL propagation
  • Configure conditional label advertising

Config

mpls ldp router-id interface [force]

router(config-if)# mpls ip

router(config-if)#mpls label protocol [tdp|ldp|both]   #!IOS v12.4(3) the default is now ldp – tdp was previously

router(config-if)#mpls mtu bytes

router(config)#mpls ip propagate-ttl [forwarded | local] #\ default is enabled

router(config)#mpls ldp advertise-labels [for <prefix-acl> [to <peer-acl>]]

Show/Debug Commands;

sh mpls ldp parameters
show mpls interfaces
show mpls ldp discovery
sh mpls ldp neighbor
sh mpls ldp neighbor detail
sho mpls ldp bindings
show mpls forwarding-table
sh ip cef detail

debug mpls ldp ….
debug mpls lfib ….
debug mpls packets [interface]