Software RAID, by definition, utilizes the host system's main processor (CPU) and system memory (RAM) to perform all RAID calculations and manage the virtual disk. This implementation integrates the RAID logic into the operating system's kernel or a driver. Unlike hardware RAID, it does not rely on a dedicated, specialized processor or cache on an adapter card. Dell's S-series controllers (e.g., S160) are examples of software RAID solutions that leverage the server's embedded processing and memory resources.

A. Software RAID is not restricted to write-through mode; it can support write-back caching, though this poses a data integrity risk without system-level power protection.

C. NVRAM is a component typically found on hardware RAID controllers to protect write cache data during a power failure; the RAID logic does not execute on it.

D. A PERC H965 is a high-performance hardware RAID controller featuring a dedicated RAID-on-Chip (ROC) processor and cache, which offloads RAID tasks from the host system.

1. Dell PowerEdge S160 User's Guide

Page 5

Section: "Introduction". The document states

"The S160 controller is a software RAID solution... The S160 controller uses the resources of the host CPU and memory." This directly supports the correct answer (B).

2. Dell PowerEdge RAID Controller 12 User's Guide

Page 6

Section: "PERC 12 family of controllers". This guide describes the PERC H965i as a "high-performance RAID controller with RAID-on-Chip (ROC) and 16 GB of DDR4 Non-Volatile cache memory." This confirms it is a hardware RAID solution

directly refuting option (D) and clarifying the role of NVRAM/NVCache (refuting C).