As shown in Figure: Failure scenario 1, when ASBR-3 fails, ASBR-1 detects the failure using ASBR MoFRR and enables the primary backup path (P-B). This is the case for every LSP that has been set up for ASBR MoFRR in any AS.
Figure: Failure scenario 1
In another example, as shown in Figure: Failure scenario 2, failure on ASBR-1 causes the attached P router to generate a route update to the leaf, removing the ASBR-1 from the routing table and causing an ASBR-MoFRR on the leaf node.
Figure: Failure scenario 2
