Storage Services, Data Protection, and Resiliency
What the domain tests
Storage Services, Data Protection, and Resiliency covers how Nutanix stores data safely, how snapshots and replication work, and how RPO and RTO drive design.
Core rules
- Replication Factor (RF2/RF3) protects against node or disk failure by keeping copies. It is not a backup.
- Erasure coding (EC-X) reduces capacity overhead for cold data; it improves capacity efficiency, not RPO.
- Inline deduplication and compression reduce physical footprint; they are storage efficiency features.
- Snapshots are lightweight, metadata-based point-in-time copies. Protection Domains group VMs and volumes for consistent snapshots and replication.
- Async replication provides a scheduled RPO, often hourly. NearSync provides a much lower RPO in the minutes range. Metro Availability provides synchronous, zero-RPO across sites with stretched clusters.
- Nutanix Leap and Xi Leap provide DR orchestration and DR-as-a-service options.
Worked example
An application needs RPO of 5 minutes and RTO of 30 minutes. Hourly async replication fails the RPO requirement. NearSync is a better fit because it replicates changes frequently; Metro could provide zero RPO but requires a stretched cluster and low-latency links. The reasoning: choose the least complex technology that meets both RPO and RTO, not the highest availability option by default.
Traps
Do not call RF2 a backup. Do not assume snapshots are independent copies on another site. Do not confuse RPO (data loss tolerance) with RTO (downtime tolerance). Do not assume EC-X improves performance; it is primarily a capacity feature.