PowerScale Platform Fundamentals
Domain overview
PowerScale Platform Fundamentals tests the architecture that makes a PowerScale cluster behave as one scale-out NAS system rather than a collection of servers. Expect questions on OneFS, node families, the single namespace, data layout, licensing, and the difference between cluster-level and node-level concepts.
OneFS and the cluster
- OneFS is the distributed file system and operating system that runs on every node. Each node is a peer: there is no dedicated metadata head node, and every node can serve data and metadata.
- A cluster presents one namespace and one IP namespace through SmartConnect. Directories and files are striped across nodes; the cluster, not an individual node, is the unit of management.
- OneFS separates front-end client traffic from back-end intra-cluster traffic. Back-end links carry data and metadata between nodes and must never be used for client mounts.
Hardware families
- F-series is all-flash for low-latency and metadata-heavy workloads. H-series is hybrid for general file services. A-series is archive-oriented for capacity and infrequent access. Older P- and X-series appear in legacy environments.
- Node choice is a planning decision: all-flash for performance, hybrid for balance, archive for cold data. A cluster can mix families, and SmartPools can move data between tiers.
Licensing and services
- Base OneFS provides the core file system and protocols. Optional licenses include SmartConnect Advanced, SnapshotIQ, SyncIQ, SmartQuotas, SmartPools, CloudPools, and InsightIQ.
- Access zones provide separate authentication and share/export namespaces for tenants or environments. Groupnets, subnets, and IP pools define client addressing.
Worked example
A customer needs a single namespace for 200 TB of engineering files with frequent metadata operations and a second copy for disaster recovery. Choose F-series nodes for the active cluster because all-flash reduces metadata latency; use H-series only if cost per TB dominates. Size for protection overhead, not raw capacity, and license SyncIQ for replication. SmartConnect is needed for a single client-facing name, but it does not replace DNS delegation.
Traps
- Treating a node as a standalone NAS: shares, exports, and snapshots are cluster objects.
- Assuming OneFS uses traditional RAID: protection is cluster-wide and node-aware.
- Forgetting that optional features such as SmartConnect Advanced, SnapshotIQ, and SyncIQ require licenses.
- Confusing access zones with VLANs; they are authentication and namespace boundaries.