During an NDB upgrade, the upgrade process follows a specific order to maintain stability and HA. The Leader NDB API Server is upgraded first. This server coordinates API requests and ensures the control plane remains operational. Upgrading the leader first minimizes disruption, as subsequent components (e.g., other API servers, HAProxy) rely on its leadership role. Once the leader is upgraded, the remaining NDB HA control plane VMs (e.g., follower API servers, HAProxy) are updated in sequence.
Other options are incorrect:
A. NDB Server: Refers to the main NDB instance, not upgraded first.
C. Leader HAProxy: Upgraded after API servers to maintain load balancing.
D. NDB Agent VMs: Upgraded last, as they are client-side components.
Thus, the verified answer is B, reflecting the upgrade sequence.
Official Nutanix Database Automation References
Nutanix Database Management & Automation (NDMA) course, Module 2: Deploying and Configuring an NDB Solution, Lesson 2.4: Updating NDB.
Nutanix Certified Professional - Database Automation (NCP-DB) v7.5Knowledge Objectives, Section 2: Deploy and Configure an NDB Solution, Objective 2.3: Perform NDB Updates (applicable to v7.5).
Nutanix NDB Administration Guide: "NDB Upgrade Process" section.
