Creating separate storage pools based on media type (e.g., NVMe for high-performance, SAS SSD for capacity/throughput) is a core PowerFlex design best practice. It physically isolates the performance characteristics and I/O patterns of different workloads. QoS (A) can help but doesn’t prevent noisy neighbors at the physical media level. Protection domains (C) are for fault isolation, not performance isolation. Different replication factors (D) affect availability and capacity, not fundamental performance tiers.

A high ‘Pending Writes’ counter on a single SDS typically indicates that writes are being accepted by the SDS but are delayed in being persisted to the underlying storage. The most common cause is a network issue (latency, packet loss, congestion) on the link between the SDC and that specific SDS, as this slows down the replication process. Checking network infrastructure is the logical first step. While a failing drive (B) or host resource issue (D) are possible, they are less specific to the ‘Pending Writes’ symptom. An MDM connection loss (C) would cause broader failures, not just pending writes.

A fundamental benefit of PowerFlex’s scale-out, software-defined architecture is its ability to scale granularly and non-disruptively. Adding new SDS nodes (servers with drives) to an existing cluster allows the system to automatically incorporate the new resources. Background tasks like rebalancing and rebuilding then intelligently redistribute data to optimize layout and performance across the now-larger cluster, all without application downtime. The other options describe disruptive, manual, or incorrect processes not native to PowerFlex’s design.

With RF=3, data is written to three different SDS nodes. Losing two SDS nodes means that for some data chunks, only one copy remains. This violates the defined protection policy (RF=3). To prevent data corruption or loss from a subsequent write to a single copy, PowerFlex places the affected storage pool into a ‘Faulty’ state and stops all I/O. This is a safety mechanism. The pool does not automatically downgrade its RF (D), become read-only (B), or remain fully functional (A); it requires administrator intervention to resolve the fault condition.

Network redundancy is critical for a highly available PowerFlex system. While separate physical switches (A) and jumbo frames (B) are strong best practices for performance and isolation, they are not strictly mandatory. A common Layer 2 domain (C) is not required; routed networks are supported. However, configuring network interface bonding/teaming (like LACP) on each node for the data network is a mandatory requirement in production. This ensures path redundancy and prevents a single NIC or cable failure from taking a node offline, which is essential for maintaining data availability.

The storage pool’s underlying media type is the primary determinant of baseline latency. A pool built from NVMe drives will provide significantly lower latency than one built from SAS or SATA SSDs or HDDs. Compression (B) adds computational overhead and can increase latency. Thick vs. Thin provisioning (C) relates to capacity allocation, not performance. Volume size (D) does not directly correlate to latency; PowerFlex’s performance comes from the distributed architecture and media, not per-volume caching.

PowerFlex does not have a recycle bin or instant ‘Undelete’ function for volumes (D). Without a pre-existing snapshot (C is false for this scenario) or a clone, the only reliable recovery method is from an external backup. Remapping (B) is not a valid concept for recovering deleted data. Therefore, restoring from backup (A), while potentially time-consuming, is the correct and safest procedure. This highlights the importance of integrating PowerFlex with a backup solution or using its native snapshot/clone features for data protection.

Using VMware Virtual Volumes (VVols) via the PowerFlex vSphere Plugin is a modern, scalable, and feature-rich integration method. It aligns each virtual disk with a native PowerFlex volume, enabling granular management, snapshots, and replication at the VM-disk level. Using a single large VMFS datastore (B) is a legacy method that loses this granularity. Using RDMs (A) is generally not recommended for scale. Installing the SDC in the guest OS (D) is a valid model (the ‘in-guest’ model) but is less common for general VM workloads and bypasses vSphere storage services.

This is a fundamental architectural concept. A Protection Domain (PD) is a group of SDS nodes that share a common failure domain (e.g., a rack). Its purpose is to isolate faults. Within a PD, you create one or more Storage Pools, which are logical groupings of physical devices (from the SDS nodes in that PD) that have similar media types (e.g., NVMe, SSD). Therefore, PDs contain Storage Pools, not the other way around. A Storage Pool cannot span multiple PDs.

Creating separate storage pools based on media type (e.g., NVMe for high-performance, SAS SSD for capacity/throughput) is a core PowerFlex design best practice. It physically isolates the performance characteristics and I/O patterns of different workloads. QoS (A) can help but doesn’t prevent noisy neighbors at the physical media level. Protection domains (C) are for fault isolation, not performance isolation. Different replication factors (D) affect availability and capacity, not fundamental performance tiers.0