In Nutanix Era, a Volume Group is the recommended storage provisioning method for a large I/O- intensive database that doesn't support a multi-disk layout1. A Volume Group in Nutanix Era is a collection of disks that can be managed as a single entity, providing a way to aggregate the storage capacity of multiple disks into a larger storage unit1. This allows for better performance optimization as it enables the database to leverage the combined I/O capabilities of all the disks in the group1. It's important to note that while other options like Load Balancing, Storage Spaces, and vDisk based provisioning can also be used in certain scenarios, a Volume Group is specifically designed for situations where a single, high-performance storage unit is required1.