KNOWLEDGE CENTRE / SERVERS / STORAGE

Server Storage: HDD vs SSD

Choosing server storage involves balancing capacity, performance, workload requirements and resilience.

Hard drives and SSDs can both be appropriate in server environments. The correct choice depends on what the storage will be used for.

Practical example: NAS, DAS or SAN?

25-user storage example
25-user storage exampleFor shared office files, NAS is often the natural architecture to evaluate first. RequirementShared filesDASOne-host focusNASFile services over LANSANShared block storage For shared office files, NAS is often the natural architecture to evaluate first.

For shared office files, NAS is often the natural architecture to evaluate first.

Scenario: A 25-user office needs shared departmental files, central backup storage and controlled user access.

A NAS is a natural candidate because it provides file services over the existing network. A directly attached enclosure would tie the storage more closely to one host. A SAN would make more sense where servers require shared block storage, for example in a more complex virtualisation environment.

Decision: For this example, start by evaluating NAS capacity, drive type, network speed, snapshots and backup replication. Do not deploy SAN architecture merely because it sounds more enterprise.

Common mistakes and selection checklist

Common mistakes

  • Choosing NAS, DAS or SAN because one architecture sounds more enterprise rather than because it fits the workload.
  • Sizing storage only by terabytes and ignoring IOPS, throughput, network speed, snapshots and backup.
  • Using one storage system as both primary data and the only backup copy.

What happens if you get it wrong?

Users can experience slow file access or applications can be constrained by the wrong storage path. More importantly, a storage failure or data-loss event can affect both production data and the supposed recovery copy.

Selection checklist

  • Decide whether applications need file storage, block storage or storage attached to one host.
  • Estimate current usable capacity and realistic growth.
  • Identify performance, network and concurrency requirements.
  • Check drive type, RAID options, snapshots and expansion.
  • Design backup and off-system recovery independently.

Hard disk drives

HDDs use rotating magnetic media and can provide substantial capacity. They remain useful where capacity and cost per unit of storage are important considerations.

Solid-state drives

SSDs use flash storage and have no spinning mechanical media. They can provide substantially different performance characteristics and are often attractive for workloads that generate frequent random I/O.

Performance is not the only consideration

Capacity, endurance, interface, workload, RAID configuration and budget all influence the storage decision.

Use the right drive for the server

Server drives are available in different interfaces and specifications. Compatibility with the server, controller and intended workload needs to be checked.

ConsiderationHDDSSD
TechnologyRotating magnetic mediaFlash storage
Capacity focusOften strong for high-capacity storageCapacity varies by model
Random I/OMechanical limitationsTypically much lower access latency
WorkloadCapacity-focused workloadsPerformance-sensitive workloads
How to use this information

Confirm the exact product specification, supported configuration and compatibility before ordering. Platform generation, firmware, licences and optional components can change what a product supports.