Cisco Nexus 7000 Series Configuration Manual page 52

Fabric Overlay Control-Plane (MP-BGP EVPN)
shown in the image below). Since MP-BGP enables isolation of groups of interacting agents, VMs/servers
that belong to the same tenant are logically isolated from other tenants.
Figure 7: End Host IP + MAC Address Distribution in a VXLAN Setup
The reasons for using BGP EVPN continues below:
• Reduce flooding
• Distributed Anycast Gateway
• VM Mobility Support
Cisco Nexus 7000 Series NX-OS VXLAN Configuration Guide
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• Since the number of end hosts attached to VTEPs in a data center is huge, a mechanism is required
to reduce flooding for discovery of end host location and resolution information. This is achieved
via MAC/IP binding information distribution.
• MAC address distribution eliminates (or reduces) unknown unicast flooding because MAC addresses
are prepopulated.
• MAC to IP binding information helps in local ARP suppression.
• For a given subnet, the same default gateway with the same IP and MAC address is realized
simultaneously on appropriate ToR switches thereby ensuring the default gateway for the end hosts
is always at its closest point aka its directly attached switch.
• This ensures that routed traffic is also optimally forwarded within the fabric without going through
any tromboning.
• The control plane supports transparent VM mobility and quickly updates reachability information
to avoid hair-pinning of east-west traffic.
Configuring VXLAN BGP EVPN