Objectives
The simulator ticks each one as soon as the network meets it.
The fabric has no ASN, so the session to R1 is down too: set asn 65000 under bgp-fabric.
Route reflector 101 is a leaf: remove it, and make spines 201 and 202 route reflectors.
show bgp sessions on L102 lists both spines, and PC1 reaches 10.100.100.1.
Before you start
R1 expects AS 65000 from the fabric, and that’s the one ASN the whole fabric shares. Fix the ASN first and the L3Out comes up, but L101 still has no route until the reflectors are right: two faults with one symptom.
Concept
ACI: fabric BGP and route reflectors
A leaf that learns an outside route must tell the other leaves. Fabric BGP does that: every switch shares one ASN, spines act as route reflectors, and each leaf peers only with those spines. Without it, an L3Out’s routes stay on its border leaf, and hosts elsewhere have no way out.
