Summary

This chapter builds on the comprehensive TI-LFA node + SRLG protection scenario presented in the previous chapter, with the objective of exploring scenarios where TI-LFA cannot offer all the requested protection mechanisms simultaneously. This situation requires the PLR to decide which protection mechanism takes precedence.

The Cisco IOS-XR platform allows for the configuration of node and SRLG protection using tiebreaker index values. Although these index values were introduced in previous chapters, their significance is emphasized in this chapter. The index values help TI-LFA on a router determine which protection mechanism to prefer when not all requested protections can be offered simultaneously. A lower index indicates a higher preference for that protection.

To explore the tiebreaker scenarios, an additional router, P9, was integrated into the existing topology. The configuration required to integrate P9 adheres to the same principles used for other routers, including...