An administrator needs to roll back an Oracle patch on a database server VM using...

To roll back an Oracle patch on a database server VM using NDB, the patch must have been applied using NDB in the first place. This is because NDB maintains a patch inventory and history for each database server VM and database that it manages. NDB uses this information to determine which patches can be rolled back and how to revert the changes made by the patch. If the patch was applied outside of NDB, NDB would not have the patch information and would not be able to roll back the patch. Therefore, the patch must have been applied using NDB for the rollback action to be successful. The other options are not required for the rollback action. The database does not need to be shut down or in read-only mode, as NDB can perform the rollback operation online. The patch does not need to be applied on Grid home only, as NDB can roll back patches applied on both Grid home and Database home. References:

Nutanix Certified Professional - Database Automation (NCP-DB) v6.5, Section 4 - Operate and Maintain an NDB Environment, Objective 4.4: Determine the correct method to apply Linux OS patches

Nutanix Database Management & Automation (NDMA) Course, Module 5: Nutanix Database Service (NDB) Patching, Lesson 5.1: Patching Overview, Topic: Patching Concepts

[Nutanix Database Service (NDB) User Guide], Chapter 7: Patching, Section: Rolling Back a Patch