To enable iSCSI connections between the Nutanix Database Service (NDB) server, Controller VMs (CVMs), and Prism Element, a Data Services IP must be configured in Prism Element. The Data Services IP acts as a cluster-wide address that facilitates iSCSI target discovery and connectivity. It is used by Nutanix Volumes (a block storage service) to present storage to external clients or services, such as the NDB server, via the iSCSI protocol. This IP ensures that iSCSI traffic is routed correctly and remains available even if a CVM fails, as ownership of the Data Services IP can move to another CVM in the cluster.

Configuring the Data Services IP is a prerequisite for integrating NDB with a Nutanix cluster, as NDB relies on iSCSI to manage database storage operations like provisioning and cloning. Without this configuration, the NDB server cannot establish the necessary connections to the CVMs for database-related tasks. Options like Virtual IP, Secondary DNS IP, and Backplane IP are not relevant in this context:

Virtual IP: This is typically associated with high-availability setups for applications, not iSCSI connectivity.

Secondary DNS IP: This pertains to network resolution, not storage connectivity.

Backplane IP: This is an internal network IP for cluster communication, not for external iSCSI access.

Thus, the correct and verified answer is the Data Services IP.

Official Nutanix Database Automation References

Nutanix Database Management & Automation (NDMA) course, Module 2: Deploying and Configuring an NDB Solution, Lesson 2.2: Configuring NDB Prerequisites.

Nutanix Certified Professional - Database Automation (NCP-DB) v7.5Knowledge Objectives, Section 2: Deploy and Configure an NDB Solution (applicable to v7.5 as foundational concepts remain consistent).

Nutanix Support & Insights Portal: "Configuring iSCSI Data Services IP for Nutanix Volumes" (general Volumes configuration applicable to NDB).