In a VXLAN BGP EVPNMulti-Siteenvironment:

DCI trackingmonitors the health of the DCI links. If all DCI-tracking interfaces go down, the leaf can incorrectly keep advertising or learning remote MAC/IP reachability, leading to packet loss and sub-optimal forwarding for servers in that VLAN/L2VNI.

For proper operation, eachDCI-facing interfacemust be enabled with evpn multisite dci-tracking so that the Multi-Site border leaf tracks reachability over that link.

When using EVPN Multi-Site, BUM (broadcast, unknown unicast, multicast) traffic toward remote sites is typically handled viaingress replication, not multicast groups, for each L2VNI participating in Multi-Site. The configuration snippet shows an L2VNI (vn-segment 16535) still mapped to mcast-group 239.1.1.0, which is inconsistent with Multi-Site recommendations and contributes to packet loss.

Therefore, to fix the problem:

Enable DCI tracking on the uplink:

interface Ethernet1/1

evpn multisite dci-tracking

This restores proper DCI-link state monitoring for Multi-Site. →Option C

Change the L2VNI behavior from multicast to Multi-Site ingress replication:

Under the VNI for VLAN 11, configure:

evpn

vni 16535 l2

multisite ingress-replication

or the equivalent command for the specific NX-OS release, thereby aligning the L2VNI with EVPN Multi-Site design and eliminating packet loss. →Option D

Options A and B are ELAM (embedded logic analyzer) filters used only for packet capture and do not resolve the forwarding issue.

Option E is an ACL line unrelated to EVPN VXLAN or DCI tracking and does not address the underlying problem.