Referring to the exhibit, which configuration change should be made to solve the problem?

Exhibit.

You are troubleshooting a DCI connection to another data center The BGP session to the provider is established, but the session to Border-Leaf-2 is not established.

Referring to the exhibit, which configuration change should be made to solve the problem?
A . set protocols bgp group overlay export loopbacks
B . delete protocols bgp group UNDERLAY advertise-external
C . set protocols bgp group PROVIDER export LOOPBACKS
D . delete protocols bgp group OVERLAY accept-remote-nexthop

View Answer

Answer: D

Explanation:

Understanding the Configuration:

The exhibit shows a BGP configuration on a Border-Leaf device. The BGP group UNDERLAY is used for the underlay network, OVERLAY for EVPN signaling, and PROVIDER for connecting to the provider network.

The OVERLAY group has the accept-remote-nexthop statement, which is designed to accept the next-hop address learned from the remote peer as is, without modifying it. Problem Identification:

The BGP session to Border-Leaf-2 is not established. A common issue in EVPN-VXLAN environments

is related to next-hop reachability, especially when accept-remote-nexthop is configured.

In typical EVPN-VXLAN setups, the next-hop address should be reachable within the overlay network. However, the accept-remote-nexthop can cause issues if the next-hop IP address is not directly reachable or conflicts with the expected behavior in the overlay. Corrective Action:

D. delete protocols bgp group OVERLAY accept-remote-nexthop: Removing this command will ensure that the device uses its own IP address as the next-hop in BGP advertisements, which is standard practice in many EVPN-VXLAN setups. This change should help establish the BGP session with Border-Leaf-2.

Data Center

Reference: Proper handling of BGP next-hop attributes is critical in establishing and maintaining stable BGP sessions, especially in complex multi-fabric environments like EVPN-VXLAN. Removing accept-remote-nexthop aligns with best practices in many scenarios.