This is indeed a big problem if you're using non-EVPN devices in your fabric. You will need to enable manual MAC address override as smicker suggested. In terms of how this impacts traffic, it's important to understand the forwarding behavior. The leaf will install the next-hop for the ESI gateway segment if the VGA MAC is used. Meaning the leaf will load-balance to the gateway devices (per flow). If the unicast MAC is used, then you will not load-balance, rather you will send traffic directly on the VTEP tunnel. Although you will still load balance in the fabric.
I did write a little article on how load-balancing works >
EVPN-VXLAN | Virtual Gateway |QFX5k Forwarding | JUNOS – DAN HEARTY (wordpress.com)------------------------------
DANIEL HEARTY
Principal Engineer
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Original Message:
Sent: 11-21-2021 06:27
From: Unknown User
Subject: EVPN VGAs Virtual MAC address to originate packets
Hi! Experts
By default, the IRB interface in EVPN does not use VGAs' Virtual MAC address (00:00:5e:00:01:01) to originate packets, it use interface real MAC address to originate packets instead .
Are there any special thoughts behind this? cause it will cause BUM flooding if peer is a layer 2 switch.
Thanks for your help!