What is the primary function of a Fault Domain in OCI?

The primary function of a Fault Domain in Oracle Cloud Infrastructure (OCI) is to isolate resources within availability domains. Fault domains are essentially logical grouping partitions inside an availability domain that help distribute resources in a way that enhances their reliability and availability. Each fault domain is independent and can experience hardware failures or planned maintenance without affecting resources in other fault domains within the same availability domain.

By utilizing fault domains, customers can architect their applications for improved resilience against localized failures. This means that if one fault domain goes down, the resources in other fault domains can continue to operate, reducing the risk of total application outages. Deploying resources across multiple fault domains is a best practice for achieving high availability in cloud applications.

In contrast, options related to enhancing storage efficiency, increasing access speed, or managing high availability do not directly pertain to the specific role of fault domains, which focus on isolation to better withstand potential disruptions within an availability domain.