HPE 635335-001 600GB 10K RPM SAS 2.5 INCH Small Form Factor SFF 6GB/S HDD

Quick specification snapshot

• Manufacturer / OEM part: HPE / 635335-001 (cross-references: 613922-001, AW611A/B depending on packaging).
• Capacity: 600 GB raw.
• Form factor: 2.5-inch (SFF) low-profile, hot-pluggable carrier support.
• Interface: SAS (Serial Attached SCSI), 6 Gb/s (SAS-600) typical; some modern HPE families support 12G variants in similar capacities. :contentReference[oaicite:1]{index=1}
• Spindle speed: 10,000 RPM, enterprise performance-class rotational speed.
• Average latency / seek: Typical average latency ~2 ms and seek times in low single-digit milliseconds (vendor/series dependent). :contentReference[oaicite:2]{index=2}
• Hot-swap: Yes — compatible with HPE hot-pluggable trays and carriers when properly specified.

choose a 600GB 10K SAS SFF drive

This drive class occupies the mid-tier in enterprise storage architectures: it offers considerably better random I/O performance than nearline 7,200 RPM drives at a substantially lower cost-per-GB than all-flash arrays. The balance makes the 635335-001 ideal for environments that need predictable mechanical performance (virtual machine datastores, database log volumes, application servers) without paying SSD price-per-GB for entire datasets. Use it as a capacity/performance compromise in hybrid designs where SSDs cache hot data and 10K SAS supplies the larger working set.

Detailed technical breakdown

Form factor & mechanical design

The 2.5" SFF footprint allows increased drive density in blade enclosures and high-density 1U/2U server drawers. Compared to 3.5" LFF drives, SFF drives support more spindles per enclosure, reduced power draw per drive and lower physical vibration per bay when properly supported by the chassis. For rack-scale designs this means more usable IOPS per rack unit and greater aggregate bandwidth within tight physical constraints.

Interface & signalling

The drive uses a Serial Attached SCSI (SAS) interface with a typical external signaling rate of 6 Gb/s (SAS-600) for the models commonly cross-referenced with 635335-001. SAS provides enterprise-grade features such as multipath I/O, robust error detection and (on dual-port models) redundant controller connectivity for SAN-class availability. Confirm whether the specific unit you buy is single- or dual-port if you require multipath SAN topologies.

Performance profile

At 10,000 RPM, expect materially lower rotational latency compared with 7,200 RPM drives. That rotational advantage — combined with enterprise servo and head technology in this family — yields better random IOPS and faster average seek times, which are significant for workload types dominated by small random I/O (VM boot storms, metadata lookups, OLTP). Absolute IOPS will vary by RAID level, controller, queue depth and workload mix; for budgeting, treat each 10K drive as a low-hundreds IOPS device under realistic mixed loads and test with your workload traces where possible.

Thermal and power characteristics

Enterprise SFF drives are tuned for sustained operation in server environments: review the vendor datasheet for precise idle and active power draw, typical operating temperature ranges and recommended airflow rates per bay. Adequate cooling and chassis airflow are essential to maintain MTBF and to avoid thermal throttling within dense drive packs. When retrofitting into older arrays, verify enclosure cooling specs and plan for incremental power and cooling capacity.

Compatibility & supported platforms

HPE arrays and server families

The 635335-001 is frequently listed as compatible with HPE EVA M6625 and related StorageWorks/EVA platforms and is cross-referenced with multiple OEM SKUs used in those product lines. It is often found in reseller listings and refurbishment inventories targeted for EVA and server refresh projects. For full compatibility and supportability (including firmware expectations), always consult the HPE compatibility matrix or platform-specific support documentation before large-scale deployment.

RAID controllers and multipath considerations

SAS drives interact with RAID controllers and HBAs at the firmware level. Some controllers impose restrictions or mark unsupported drive families with warnings; others may permit operation but flag reduced functionality. In SAN or dual-controller arrays, prefer dual-port SAS drives and a validated drive family to maintain multipath resilience and predictable rebuild behavior. Verify that your controller firmware is up to date and that the chosen drive FRU is listed for the controller/enclosure combination.

Common use cases & architectural placements

Virtualization datastores

• Role: capacity-oriented VM datastores where predictable latency is required but full flash is not affordable.
• Configuration example: RAID 10 across multiple 600GB 10K drives with a separate SSD cache layer for hot blocks.
• Benefits: improved random IOPS over NL-SAS with better $/GB vs SSD-only pools.

Database and transaction tiers

• Role: log volumes, small high-churn tablespaces and mid-tier indexes.
• Recommended: RAID 10 or mirrored RAID for low latency and fast rebuild characteristics; controller with protected write cache.
• Why: consistent latency and improved seek performance support OLTP use reasonably well without SSD costs.

Hybrid tiered storage

Use the 635335-001 as a mid-tier in a three-tier architecture: SSD (hot) → 10K SAS (active-cold) → 7.2K NL-SAS (cold/archive). This allows cost-efficient retention of large datasets while keeping frequently accessed objects responsive via caching and IO prioritization. Many HPE reference architectures show similar tiering approaches for mixed workloads. 

Hot-swap replacement workflow

Follow vendor and controller guidance for drive replacement: mark or off-line failing drives via the management interface, confirm automatic rebuild settings, and replace with like-for-like FRUs where possible. Maintain at least one compatible hot spare in production arrays to minimize rebuild start delay. Keep spare carriers/trays pre-configured to reduce hands-on time.

Monitoring & predictive maintenance

Integrate SMART monitoring and HPE system health tools into your monitoring stack. Track reallocated sector counts, pending sectors, read/write error rates and temperature trends. Replace drives proactively when predictive indicators consistently trend toward failure — this reduces the chance of concurrent failures during rebuilds and minimizes SLA impact.

Performance tuning & RAID guidance

Choosing RAID levels

• RAID 10: Best for mixed and write-heavy workloads; faster rebuilds and robust random I/O behavior.
• RAID 6: Higher usable capacity and dual-disk failure protection — suitable for large pools where read throughput dominates.
• RAID 5: Considered for cost-optimized read-centric pools but less favored in modern enterprise arrays due to rebuild stress on remaining spindles.

Quantity planning & spares

Plan hot spares according to array rebuild time, criticality and acceptable risk: high-criticality arrays typically keep at least one hot spare per RAID domain (or more in large configurations). Factor in procurement lead times for OEM FRUs in your region to avoid extended downtime during scale-up events. :contentReference[oaicite:18]{index=18}

Firmware, security & compliance

Firmware management

Maintain a controlled firmware update process: test updates in a lab or staging environment, follow vendor-provided firmware bundles where recommended, and update controllers and enclosures in coordinated windows. Device firmware can affect performance, SMART reporting and compatibility; mismatched or unsupported firmware may be flagged by system management tools.

Secure erase & data sanitization

For end-of-life or redeployment, use approved secure erase procedures to meet organizational and regulatory requirements. When returning drives for recertification or resale, request certificates of data destruction if required by policy. Data sanitization steps should be auditable and repeatable for compliance.

Troubleshooting & supportability

Common symptoms and first steps

• Drive dropped from array: Check controller logs, inspect SMART attributes, validate physical carrier seating and backplane connectivity.
• Slow rebuilds: Verify rebuild priority, drive temperatures, and background tasks; ensure no bottlenecked controller queue or host-side saturation.
• Intermittent I/O errors: Replace suspected failing drive after confirming logs and SMART escalation; test replacement in spare bay before re-entering production array.

When to escalate to vendor support

If drives return repeated SMART failures, non-recoverable read/write errors, or if controller/array firmware reports unsupported FRU behavior, escalate per your support contract. For HPE-supported systems, provide part numbers, serial numbers and event logs to speed triage. Maintain spare inventory and vendor RMA processes to minimize downtime for critical systems.

Extended examples & configuration templates

Example configuration — small virtualization cluster

• Hardware: 3 × 2U servers, each with 12 SFF drive bays.
• Storage: 8 × 600GB 10K SAS drives per server in RAID 10 for local VM datastore; 2 × 1.6TB SSDs for cache tier (read/write caching with controller-level policy).
• Hot spare: 1 identical 600GB 10K SAS drive per server bay pool.
• Monitoring: centralized collector for SMART events, controller logs and chassis health; automated ticketing for predictive failures.