Nokia Lab | LAB 4 LDP |


Move forward to MPLS stack. The first one is LDP.  I make emphasis on LDP session process and interaction between LIB and LFIB. I recommend you use traffic dumps and debug for investigation. 
Please check my first lab for input information.

Topology example

Lab tasks and questions:
  • Basic LDP
    • prepare basic and IGP configuration (Multi-area OSPF, area type - normal, add "system" to OSPF)
    • enable LDP on P2P interfaces
      • LDP session
        • examine LDP neighbor discovery process
          • What is the destination IP address of Hello messages?
        • examine LDP session establishment
          • What address does SR-OS router use as a transport address for LDP control plane?
        • examine Label exchange
          • What label mapping does SR-OS router generate by default?
    • LIB and LFIB
      • examine LIB and LFIB
        • What is the difference between LIB and LFIB?
        • configure ECMP 2 (e.g. on R1) and examine RT, LIB and LFIB
  • Export policy and summarization
    • create two additional loopback interfaces on R1 with addresses from the same subnet (e.g.,
      • export prefixes to LDP by policy
        • examine LFIB on R2
          • Does it contain entries with target prefixes? What about LIB?
            • What is the reason for this difference?
        • add loopback interfaces to OSPF
          • examine LIB and LFIB on R2
    • examine LFIB on R5 or R6
      • Does it contain entries with target prefixes?
    • summarize these prefixes from area 0 on R3 and R4
      • examine LFIB on R5 or R6
        • Does it contain entries with target prefixes?
          • How can we resolve this issue?
      Final configs
      Github project

      Useful debug commands
      show router ldp session
      show router ldp bindings
      show router ldp bindings active
      show router fp-tunnel-table 1 {prefix}