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New Webinar: Leaf-and-Spine Fabric Designs

Several subscribers told me they’d need more details on leaf-and-spine fabric designs. As they say: your wish is my command – the upcoming update session of the leaf-and-spine fabric architectures webinar will have more details on all possible combinations of layer-2 and layer-3 fabrics.

The first session (on March 3rd) will cover layer-3 fabrics. We’ll start with the basics:

  • How do we build a simple non-redundant layer-3 fabric?
  • How do we add server-to-network redundancy?
  • Do we really need VLANs and MLAG between ToR switches?
  • Which routing protocol should you use?
  • Is it OK to use unnumbered interfaces on the core links and why would you want to do that?
  • Why is route summarization in a leaf-and-spine fabric a bad idea?
  • Do you need links between spine switches?
  • How do you stop the traffic from traversing the fabric more than once?

After covering the basics, we’ll start a deep dive with the guest star: Dinesh Dutt, Chief Scientist at Cumulus Networks. He’ll cover the intricacies of BGP and OSPF design (for example: do you use the same AS number on all spines?) and describe how the cool features Cumulus added to the Quagga routing suite simplify the data center fabrics.

Interested? All you have to do is to register.


  1. I'm also very interested to hear your take on the layer-3 routing within Cisco's EVPN+VXLAN topology, as it's one of the few designs I know of that can give us L3VPN-like capabilities on top of a VXLAN data plane.

    It's seems to be even more interesting when combined with their slimmed down version of Tail-f NCS for overlay network provisioning which they call Virtual Topology System. I've been playing with it in the lab, and it solves the issue of maintaining consistent configuration and VNI/VLAN management across the local fabric.
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