NSX Federation in VMware Cloud Foundation (VCF) 5.2 extends networking and security across multiple VCF instances (e.g., across data centers) using a leaf-spine underlay network. The architect must recommend a physical network design that supports this. Let’s evaluate:

Option A: Use a physical network that is configured for EIGRP routing adjacency

Enhanced Interior Gateway Routing Protocol (EIGRP) is a Cisco-proprietary routing protocol. NSX Federation requires a Layer 3 underlay with dynamic routing (e.g., BGP, OSPF), but EIGRP isn’t a VMware-recommended standard for NSX leaf-spine designs. BGP is preferred for its scalability and interoperability in NSX-T 3.2 (used in VCF 5.2). This option is not optimal.

Option B: Layer 3 device that supports OSPF

Open Shortest Path First (OSPF) is a supported routing protocol for NSX underlays, alongside BGP. A Layer 3 device with OSPF could work in a leaf-spine topology, but VMware documentation emphasizes BGP as the primary choice for NSX Federation due to its robustness in multi-site scenarios. OSPF is valid but not the strongest recommendation for Federation-specific designs.

Option C: Ensure that the latency between VMware Cloud Foundation instances that are connected in an NSX Federation is less than 1500 ms

NSX Federation requires low latency between sites for control plane consistency (Global Manager to Local Managers). The maximum supported latency is 150 ms (not 1500 ms), per VMware specs. 1500 ms (1.5 seconds) is far too high and would disrupt Federation operations, making this incorrect.

Option D: Jumbo frames on the components of the physical network between the VMware Cloud Foundation instances

This is correct. NSX Federation relies on NSX-T overlay traffic (Geneve encapsulation) across sites, which benefits from jumbo frames (MTU ≥ 9000) to reduce fragmentation and improve performance. In a leaf-spine design, enabling jumbo frames on all physical network components (switches, routers) between VCF instances ensures efficient transport of tunneled traffic (e.g., for stretched networks). VMware strongly recommends this for NSX underlays, making it the best recommendation.

Conclusion:The architect should documentD: Jumbo frames on the components of the physical network between the VMware Cloud Foundation instances. This aligns with VCF 5.2 and NSX Federation’s leaf-spine design requirements for optimal performance and scalability.

References:

VMware Cloud Foundation 5.2 Architecture and Deployment Guide (Section: NSX Federation Networking)

NSX-T 3.2 Reference Design (integrated in VCF 5.2): Leaf-Spine Underlay Requirements

VMware NSX-T 3.2 Installation Guide: Jumbo Frame Recommendations