Dell EMC SmartFabric OS10 User Guide Release 10.5.0

BGP EVPN with VLT

OS10 supports BGP EVPN operation between VLT peers that you configure as VTEPs. For more information about configurations and best practices to set up VLT for VXLAN, see Configure VXLAN — Configure VLT. This information also applies to BGP EVPN for VXLAN.

Dell EMC recommends configuring iBGP peering for the IPv4 address family between the VTEPs in a VLT pair on a dedicated L3 VLAN that is used when connectivity to the underlay L3 network is lost. It is NOT required to enable the EVPN address family on the iBGP peering session between the VTEPs in a VLT pair because EVPN peering to the spine switch is performed on Loopback interfaces.

In an EVPN configuration, increase the VLT delay-restore timer to allow for BGP EVPN adjacency to establish and for the remote MAC and neighbor entries to download by EVPN and install in the dataplane. The VLT delay-restore determines the amount of time the VLT LAGs are kept operationally down at bootup to allow the dataplane to set up and forward traffic, resulting in minimal traffic loss as the VLT peer node boots up and joins the VLT domain.

For a sample BGP EVPN VLT configuration, see Example: VXLAN with BGP EVPN.