Nutanix NearSync replication provides low RPOs (1 to 15 minutes) by using " Lightweight Snapshots " (LWS). NearSync has higher performance and hardware requirements than standard Asynchronous replication because it must handle metadata operations and data transfers much more frequently.

For a cluster to support NearSync, it must have sufficient high-performance storage to handle the additional I/O load associated with LWS. On hybrid nodes (those with both SSDs and HDDs), Nutanix has a specific hardware requirement: each node must have at least two SSDs. This is because the NearSync LWS metadata and incoming replicated data are initially written to the SSD tier to ensure low latency and high throughput. A single SSD per node is typically insufficient to handle both active VM production I/O and the high-frequency NearSync overhead without performance degradation. Therefore, adding a second SSD to each node (Option D) is the mandatory modification. While upgrading to NVMe (Option A) or adding more nodes (Option B) would also improve performance, adding a second SSD is the minimum " cost-effective " requirement specified by Nutanix engineering for NearSync support on hybrid clusters. Meeting these hardware prerequisites is essential to ensure that the cluster can maintain the 15-minute RPO without transitioning back to an hourly schedule due to resource constraints.