[kazen44]

> Please correct me if I'm wrong, but I see the "old" core/access/distribution layers still relevant. The datacenter spine/spline setup applies to networking between server racks in the data center.

this is correct. The place where spine-leaf really shines is when used in combination with evpn-vxlan. You can then encapsulate every tenant network inside a VXLAN domain and route those between your leafs switches through your spine layer.

This is basically a clos fabric which is non-blocking, and is very easy to expand horizontally. It also gives you nice features like ARP suppression[0]. These features are important in a DC fabric because ARP flooding is traffic which is not revenue generating, and should be minimized as much as possible.

For normal Enterprise/Office network, running an evpn-vxlan fabric is usually far to complex for the benefits involved.

[0] https://satishdotpatel.github.io/how-does-arp-suppression-wo...