The scenario involves a Cisco ACI fabric with 10 standalone leaf switches, and the engineer must configure only the first two leaf switches (e.g., Leaf-1 and Leaf-2) in a Virtual Port Channel (vPC) configuration. The goal is to select the appropriate vPC protection type to achieve this specific pairing while leaving the other eight leaf switches standalone.
Requirement Analysis
In Cisco ACI, vPC is used to provide active-active link redundancy and load balancing between two leaf switches connected to the same set of endpoints (e.g., servers or external devices).
The fabric contains 10 standalone leaf switches, meaning no pre-existing vPC pairs are configured, and the task is to form a vPC specifically between the first two leaf switches.
The vPC protection type determines how the pair is defined and protected within the ACI fabric, ensuring the configuration is limited to the intended switches.
Option Evaluation
[: Cisco ACI vPC Configuration Guide (no mention of "serial" protection)., B. explicit: , The "explicit" vPC protection type allows the engineer to manually specify the exact pair of leaf switches to form a vPC. In this case, the engineer can configure Leaf-1 and Leaf-2 as an explicit vPC pair, leaving the other eight leaf switches standalone. This method provides precise control over which switches are paired, aligning with the requirement to configure only the first two., Reference: Cisco APIC vPC Deployment Guide, "Explicit vPC Protection Group Configuration" and Cisco ACI Best Practices, "vPC Pairing.", C. reciprocal: , The "reciprocal" protection type is not a standard vPC protection option in ACI. This term might imply mutual protection, but it is not documented as a specific vPC configuration mode in ACI., Reference: No reference in Cisco ACI vPC documentation., D. consecutive: , The "consecutive" protection type is not a recognized vPC protection option in ACI. It might suggest pairing switches based on their IDs (e.g., consecutive node IDs), but ACI does not use this as a formal protection mechanism. The fabric could interpret this incorrectly, potentially pairing unintended switches., Reference: No reference in Cisco ACI vPC Configuration Guide., Final Answer Justification, B is correct because the "explicit" vPC protection type allows the engineer to manually designate Leaf-1 and Leaf-2 as a vPC pair, ensuring that only these two switches are configured in a vPC while the remaining eight leaf switches remain standalone. This method provides the precision needed to meet the goal and is a standard feature in ACI vPC deployments., Primary Cisco References: , Cisco APIC Layer 2 Networking Configuration Guide, "Configuring vPC with Explicit Protection.", Cisco ACI Design Guide, "vPC Deployment Options.", Cisco ACI vPC Best Practices, "Explicit vPC Pair Configuration.", ]
