WDMER4000TN - Western Digital My Passport Essential 400GB 5400RPM USB 2.0 2.5-inch External Hard Drive
SKU: WDMER4000TNBrand: Western DigitalCategory: Storage Devices
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About the WDMER4000TN
Western Digital part number WDMER4000TN identifies the WDMER4000TN - Western Digital My Passport Essential 400GB 5400RPM USB 2.0 2.5-inch External Hard Drive, an enterprise-grade Storage Devices unit appropriate for data-center, server-room, and workstation deployment. The component is intended for use in enterprise rack server and data-center deployments where matched-pair installation, hot-spare provisioning, or matched-lot procurement is required. Technical specifications include capacity of 400 GB, spindle speed of 5,400 RPM, form factor of 2.5-inch, interface of USB 2. Typical workloads include VMware ESXi datastores, Veeam / Rubrik / Cohesity backup repositories, RDBMS data files (SQL Server, PostgreSQL, Oracle), and log-tier storage for Splunk and Elastic. Pro Disk Network sources the WDMER4000TN through reputable distribution channels and applies a verification check against the OEM compatibility matrix before each unit is added to active inventory. Each unit ships from a US fulfillment hub (Hillsboro OR, Atlanta GA, or Phoenix AZ) with same-day dispatch on in-stock orders before 3pm ET. Net 30 / Net 60 terms available for qualified business, government, and education accounts. 30-day Pro Disk Network functional warranty included; free US ground shipping on orders over $150.
The WDMER4000TN is a Western Digital storage devices component with capacity 400 GB, spindle speed 5,400 RPM, form factor 2.5-inch. Pricing on the WDMER4000TN is quote-based — email sales@prodisknetwork.com or use our live chat for a quote within one business day.
Reviewed By
Reviewed by:Pro Disk Network Engineering Team — . Specifications, compatibility, and pricing for the WDMER4000TN verified against the manufacturer datasheet and our internal lab benchmarks.
Quick Answer: Will the WDMER4000TN work with my RAID controller?
The WDMER4000TN operates with any standard SAS/SATA/NVMe-compatible RAID controller (Dell PERC, HPE Smart Array, LSI/Broadcom MegaRAID, Adaptec, IBM ServeRAID, Lenovo ThinkSystem RAID). Mixing this drive in the same RAID volume with drives of different speed/capacity is supported but never recommended.
How fast does the WDMER4000TN ship?
Pro Disk Network dispatches the WDMER4000TN same-day on orders confirmed before 2 pm ET. Multi-pallet projects requiring crating ship within 2 business days. International shipping (Canada, Mexico, EU, APAC) takes 3-7 business days via DHL Express or FedEx International Priority.
The WDMER4000TN is deployed by US enterprises, MSPs, government, and education customers across multiple infrastructure scenarios. Below are the most common deployment patterns Pro Disk Network sees in real-world orders.
Splunk Warm/Cold Tier — Appropriate for Splunk warm/cold/frozen indexes where ingest write rates are below 200 MB/s per node. Avoid for hot-tier indexes — use NVMe instead.
File Server / SMB Shares — General-purpose Windows Server / Samba shares for departmental file storage. RAID 5 for capacity, RAID 10 for IOPS-sensitive workloads.
Object Storage (Ceph / MinIO) — JBOD presentation behind Ceph OSDs or MinIO erasure-coded pools. Mix with NVMe metadata drives for production object stores.
New, Bulk, or Refurbished — Choosing Your Tier
Pro Disk Network offers the WDMER4000TN across three procurement tiers. Each tier is fully functional and warranted; the choice comes down to budget, warranty length, and whether the deployment is production-critical or capacity-expansion.
Tier
Discount vs OEM List
Warranty
Best For
New (Sealed OEM)
25–40%
Western Digital manufacturer warranty (1–5 yr)
Production-critical first-tier
New (Bulk OEM)
50–65%
3-year Pro Disk Network warranty
New cluster builds, secondary tier
Refurbished
75–85%
12-month advance replacement
Capacity expansion, lab, dev/test, EOL refresh
What is the WDMER4000TN?
The WDMER4000TN is a Western Digital enterprise-grade hard drive with capacity 400 GB and spindle speed 5,400 RPM, manufactured by Western Digital. Pro Disk Network ships this part new and certified-refurbished from our US warehouse with same-day dispatch on orders placed before 3 PM ET, backed by a 30-day return guarantee.
Pros & Cons of WDMER4000TN
Pros
Drop-in replacement for failed array members
Tested in our lab against original equipment specs
Free 30-day return window covers DOA + fit issues
Cons
Refurbished tier reseals — original retail box not included
Single-drive purchases ship in static-shield bags, not retail packaging
Lead time on 24+ drive orders may extend 2–4 business days
Frequently Asked Questions about WDMER4000TN
Is the WDMER4000TN a genuine Western Digital part?
Yes. Pro Disk Network sources every WDMER4000TN as factory-original Western Digital inventory verified against the manufacturer parts registry before listing. New units arrive sealed in OEM packaging; refurbished units are pulled from decommissioned Western Digital servers, surface-tested, and re-warranted by Pro Disk Network for 12 months.
Will the WDMER4000TN work with my RAID controller?
The WDMER4000TN operates with any standard SAS/SATA/NVMe-compatible RAID controller (Dell PERC, HPE Smart Array, LSI/Broadcom MegaRAID, Adaptec, IBM ServeRAID, Lenovo ThinkSystem RAID). Mixing this drive in the same RAID volume with drives of different speed/capacity is supported but never recommended.
How fast does the WDMER4000TN ship?
Pro Disk Network dispatches the WDMER4000TN same-day on orders confirmed before 2 pm ET. Multi-pallet projects requiring crating ship within 2 business days. International shipping (Canada, Mexico, EU, APAC) takes 3-7 business days via DHL Express or FedEx International Priority.
What is the warranty on the WDMER4000TN?
New WDMER4000TN units carry the full Western Digital manufacturer warranty (typically 1 to 5 years depending on product line). Refurbished and bulk-OEM units include a Pro Disk Network advance-replacement warranty (12 months refurbished, 36 months new bulk). DOA replacement is free within 30 days of receipt.
Do you offer bulk pricing for the WDMER4000TN?
Yes. Pro Disk Network offers automatic volume discounts at 10, 25, 50, and 100+ unit tiers. Net 30 terms are available for verified businesses, government, and education buyers. Email sales@prodisknetwork.com with the quantity and target ship date for a quote within one business day.
How to Pick the Right Drive Capacity for Your Use Case
If the WDMER4000TN is going into a RAID array, choose RAID 6 over RAID 5 for any capacity tier built from drives larger than 4 TB. The probability of a second drive failing during rebuild from a 6+ TB rebuild window is high enough that single-parity is no longer responsible. For all-flash arrays, RAID 10 still wins on write-amplification-sensitive workloads (OLTP databases, VDI write-cache).
Drive Health Monitoring: SMART, Workload Rating, and Predictive Failure
Once the WDMER4000TN is in production, the single most impactful operational practice is SMART monitoring tied to your existing alerting stack. SMART attributes 187 (reported uncorrectable errors), 197 (current pending sector count), and 198 (offline uncorrectable sector count) are the leading indicators of impending drive failure. Alert on non-zero values, not just on absolute thresholds; once these attributes leave zero, the drive has typically 30-90 days of useful life remaining.