Hi All,
I am currently designing a VXLAN EVPN Multisite fabric using DCNM and I'm looking for some guidance regarding best practice for the following configuration.
In each fabric we will have two Spine switches and six Leaf switches. Two of the Leaf switches will be configured as 'Borders' in DCNM to provide connectivity to end hosts, to the WAN at L3 and to our legacy data centre network at L2 to support the migration of workloads into the fabric. The Spines between each fabric will be connected back-to-back and configured as 'Border Gateway Spines' to support Multisite L2 and L3 connectivity.
I have read a number of guides and typically all Multisite and WAN connectivity is configured on a single pair of Border Gateway switches within each fabric. In the proposed topology, the Spines will be configured as 'Border Gateway Spines' and used for Multisite, and a dedicated pair of Leaf switches will be configured as 'Borders' and used for WAN. Is this a supported topology?
As an alternative, would it be better to configure the 'Border' Leafs as 'Border Gateway' and use these for end hosts and all external fabric connectivity (WAN and Multisite?)
Also it is not really clear in DCNM what the difference is when you configure a Leaf as a 'Border' vs 'Border Gateway'?
