Western Digital WUS721204BLE6L4 Ultrastar DC Ha340 4TB 7.2K RPM SATA 6GBPS HDD

Western Digital WUS721204BLE6L4 Ultrastar DC Ha340 — enterprise-grade 4TB 7.2K SATA HDD

The Western Digital WUS721204BLE6L4 Ultrastar DC Ha340 4TB 7.2K RPM SATA 6Gbps 256MB Buffer 512e SE NP3 3.5-inch enterprise hard disk drive represents a balance of capacity, sustained throughput, and data center reliability tailored for business-critical storage environments. Built for mixed-workload datacenter use, this 4 terabyte drive combines a 7,200 RPM spindle speed with the wide compatibility of the SATA 6Gb/s interface and a large 256 MB cache buffer to deliver steady sequential throughput for archival tiers, software-defined storage nodes, hybrid flash/HDD arrays, backup appliances, and capacity-optimized servers. The Ultrastar DC Ha340 family is engineered for continuous operation, optimized for reliability and data integrity under heavy duty cycles, and designed to integrate seamlessly into rack-scale storage systems and established SAN/NAS infrastructures.

Key technical profile and what the model name means

The product identifier WUS721204BLE6L4 encapsulates essential aspects of the drive: a Western Digital Ultrastar-class device (WUS), 7,200 RPM spindle speed (72), a 4 TB capacity (1204 — indicating 4,000+ GB range), and enterprise-focused feature sets such as 256 MB cache and SATA 6Gb/s host interface. The “512e” notation signifies 512-byte emulation sectors, offering backward compatibility with legacy file systems and controllers while enabling higher areal density for increased capacity. “SE” often denotes specific series or firmware tuned for certain enterprise workloads, and NP3 references internal firmware/hardware revision intended by the manufacturer for the Ultrastar DC Ha340 series. This combination of features places the drive in the capacity/nearline class — where low total cost of ownership, predictable performance, and strong reliability characteristics are primary selection criteria.

Form factor and interface compatibility

Physically, the WUS721204BLE6L4 is a standard 3.5-inch drive, meaning it fits the majority of server and storage chassis designed for enterprise-class HDDs. The SATA 6Gb/s (SATA III) interface ensures broad host compatibility across modern motherboards, RAID controllers, and storage appliances. For datacenter architects and systems integrators, this offers straightforward deployment in both new builds and upgrades where SATA backplanes are already present. The 3.5-inch form factor also makes this drive suitable for dense storage shelves when combined with proper cooling and vibration mitigation — important considerations in multi-drive enclosures and high-drive-count arrays.

Performance characteristics and real-world throughput

With a 7,200 RPM spindle speed, the Ultrastar DC Ha340 targets a middle ground between high-capacity, lower-speed nearline drives and higher-RPM 10K/15K performance drives. The rotational speed delivers acceptable random and sequential performance for capacity-oriented tiers while keeping power and thermal footprints lower than faster spindle options. A 256 MB buffer (cache) improves short-burst write and read operations and smooths out microburst traffic patterns common in virtualization hosts and mixed transactional workloads. In practice, these attributes combine to produce steady sequential read/write throughput that benefits large file transfers, streaming archival reads, and sequential backup workloads while maintaining reasonable latency for moderate random I/O tasks when deployed in RAID groups or with caching layers such as SSD read/write caches or hybrid tiers.

Optimal deployment scenarios

The Ultrastar DC Ha340 excels when used as a capacity tier in scale-out storage clusters, object storage systems, cold or warm data repositories, and backup/archival appliances. It performs well as the primary capacity medium behind an SSD tier in hybrid arrays, where frequently accessed metadata and hot datasets are cached on flash, and bulk datasets remain resident on the HDD layer. Use cases include long-term retention for compliance data, media asset storage for content workflows, cold storage for analytics lakes, and bulk virtualization datastore growth where cost per terabyte is a significant driver. Systems architects will often pair these drives with erasure coding or RAID-6 configurations to optimize storage efficiency and resiliency at scale.

Mixed-workload readiness

While not a low-latency 15K drive or an enterprise NVMe SSD, the Ultrastar DC Ha340 is tuned for mixed workloads prevalent in modern data centers: periodic random reads and writes overlapped with heavy sequential streams. Enterprise firmware enhancements typically include command queuing optimizations, power-management features for datacenter energy efficiency, and serviceability telemetry for monitoring health and pre-failure indicators. For customers operating virtualization clusters, containerized platforms, or content distribution systems, this HDD offers a predictable, cost-effective option to expand capacity without imposing significant re-architecture costs.

Reliability, durability, and enterprise features

Reliability is the cornerstone of any enterprise-class drive, and the Ultrastar DC Ha340 series is engineered with datacenter operation in mind. Drives in this class are designed to handle continuous 24/7 workloads, long mean time between failures (MTBF) expectations, and the environmental stresses of high-density enclosures. Manufacturers of enterprise HDDs employ mechanical and firmware technologies to mitigate vibration, manage thermal behavior, and protect data integrity during power events. For systems that require high availability, redundancy through RAID, replication, and node-level failover should be combined with the drive’s built-in features and manufacturer-supplied drive health monitoring to form a resilient storage solution.

Smart monitoring and data integrity

Enterprise HDDs such as the Ultrastar DC Ha340 typically support SMART (Self-Monitoring, Analysis and Reporting Technology) attributes, which provide actionable telemetry for administrators. SMART metrics can be integrated into monitoring stacks to trigger proactive maintenance or drive replacement before failures impact workloads. Additionally, firmware-level error recovery and background media scanning help isolate and remediate latent sector errors, reducing the chance of data loss during rebuilds. These features are especially important in large arrays where rebuild times can be lengthy and the probability of encountering media errors increases with drive count.

Power management and thermal considerations

Because energy consumption and thermal management are significant operating expenses in modern datacenters, the Ultrastar DC Ha340’s design aims to deliver efficient power characteristics for a 7.2K RPM enterprise drive. Intelligent power states, spin-up behavior, and thermal throttling enable the drive to operate within expected datacenter power envelopes while maintaining service-level objectives. When deploying large numbers of these drives, administrators should plan for adequate cooling airflow and consider configuring staggered spin-up to avoid inrush current peaks that can stress power distribution systems.

Compatibility, integration, and system design

Compatibility is a major advantage for SATA-based enterprise drives: a wide range of commodity servers, storage arrays, and backplane designs accept SATA 6Gb/s devices. This enables cost-effective upgrades where legacy SATA infrastructures are in place. Integration guidance for the Ultrastar DC Ha340 includes firmware compatibility checks with RAID controllers, validation of backplane hot-swap support, and confirming that the host supports 512e sector emulation where required. Systems integrators may also verify that drive firmware versions are compatible with vendor-specific storage platforms to ensure predictability in behavior and performance.

RAID and rebuild behavior

When used in RAID arrays, particularly large-capacity RAID-6 or erasure coded groups, the Ultrastar DC Ha340’s performance during rebuilds and resilvering is critical. The 256 MB buffer aids short-burst performance, but rebuild speed depends on sustained read throughput and system architecture. Administrators can minimize rebuild windows by adopting parallel rebuild strategies, using spare SSD caches to accelerate reconstruction, or employing storage software that prioritizes critical data movement. Careful attention to rebuild policies can significantly reduce exposure to degraded redundancy states and protect business continuity.

Firmware and lifecycle management

Enterprise drive firmware is key to long-term operation. Western Digital typically issues firmware updates to address corner-case behaviors, enhance performance, or improve compatibility with storage controllers. IT teams should have a lifecycle management plan that includes periodic firmware audits, controlled update processes, and vendor coordination to ensure updates are applied safely. In hyperscale environments, firmware consistency across drive populations helps maintain stable performance and reduces the risk of unexpected behavior.