Some drive populations and models exhibit early failures, but large-scale field data do not establish that every drive's first 6-12 months have the highest failure rate across its lifespan. This early failure period is called infant mortality and is a well-documented phenomenon in hard drive reliability data. Some failing drives develop SMART or surface-error indications, but SMART does not reliably predict individual failures and a clean result does not guarantee future reliability. Testing a new drive before adding it to a NAS RAID array catches these failures while the drive is still under warranty and before it can cause data loss. The process takes between 3 and 24 hours depending on drive capacity and testing depth, and requires no specialised tools beyond what is built into Synology DSM, QNAP QTS, or free Windows software.
In short: Run a SMART extended self-test on every new drive before adding it to a NAS storage pool. On Synology: Storage Manager > HDD/SSD > Health Info > Extended Test. On current QTS: Storage & Snapshots > Storage > Disks/VJBOD > Disks > select the disk > Health > Test > Complete Test. On Windows: use SeaTools 5 for Seagate drives or Western Digital Kitfox for WD hard drives. CrystalDiskInfo can display SMART data but does not initiate an extended self-test. On a new drive, non-zero reallocated, pending, or uncorrectable-sector counts warrant manufacturer diagnostics and contacting the retailer. Warranty and Australian Consumer Law remedies depend on the diagnostic result and the circumstances of the fault.
Why New Drives Need Testing
The bathtub curve is the standard model for hard drive failure probability over time. The bathtub curve is a conceptual reliability model with early-failure, useful-life and wearout phases, but the shape and timing of those phases vary substantially by drive model, generation and operating environment.
The infant mortality period matters for NAS builds because a new 4-bay NAS with four untested drives has all four drives in the elevated-failure period simultaneously. If one drive fails and the RAID array enters a rebuild, a second drive failing during that rebuild destroys the array in RAID 5. Pre-installation testing can identify some existing defects under controlled conditions, but a passing test does not predict or guarantee future reliability.
What testing catches:
- Surface defects: sectors that fail on the first full read, indicating platter damage from shipping or marginal manufacturing
- Reallocated sectors: sectors the drive has already identified as defective and mapped to spare area. Any reallocated sectors on a brand new drive is a defect worth returning.
- Pending sectors: sectors flagged for reallocation that have not yet been successfully rewritten
- Electronics and firmware faults: drives that produce errors, disconnect, or report impossible SMART values often have electronic faults that will cause early failure
NAS-grade drives like the Seagate IronWolf and WD Red Plus carry 3-year warranties that cover replacement. The warranty does not cover the cost of professional data recovery in Australia, which starts at $500 for logical failures and can reach $5,000 or more for physical RAID recovery. Testing takes a few hours. Data recovery takes weeks and costs thousands.
Before testing: Test drives individually before they join the RAID array. Do not add an untested drive to a storage pool first and test it there. A drive that fails testing can be returned under warranty. A drive that fails in a RAID array during a rebuild can take the array down. Test first, add to the array after all drives have passed.
Step 1: Inspect the Drive Physically
Before connecting the drive, inspect the packaging and the drive itself. Hard drives are sensitive to shock during shipping, and couriers are rough with packages.
What to check:
- Packaging integrity: crushed corners, obvious impact damage, or an audible rattle from inside the box indicating a loose component
- Drive case: dents, scratches, or deformation on the drive enclosure itself
- SATA connector: bent or damaged pins on the SATA data or power connector
- Label: verify the model number against what you ordered; confirm the capacity; confirm whether the drive is CMR or SMR using the model number against community lists if recording technology matters for your use case
Photograph any packaging damage before proceeding. If the drive fails testing and you need to return it, photographic evidence of shipping damage strengthens the claim. Under Australian Consumer Law, the retailer must provide an appropriate remedy when goods fail the consumer guarantees. The remedy depends on whether the failure is major or minor. Consumers may need to pay initial return costs for readily returnable goods, but reasonable costs are generally recoverable once a fault is confirmed.
Step 2: Run the SMART Quick Test
The SMART quick test (also called a short self-test) is a 1-5 minute test run by the drive's own firmware. It checks the drive's internal circuitry, the servo mechanism, and a sample of the drive surface. It will not catch all surface defects but will immediately identify drives with obvious electronic or servo failures.
On Synology DSM:
- Open Storage Manager from the main DSM menu.
- Select the HDD/SSD tab.
- Click on the drive you want to test.
- Select Health Info.
- Choose Quick Test and click Run.
The test completes in approximately 2-5 minutes. The result is Pass or Fail. A Fail result on the quick test means the drive has a significant fault and should be returned. Do not add a failed drive to the NAS.
On QNAP QTS:
- Open Storage and Snapshots from the QTS main menu.
- Select Storage, then Disks.
- Click on the drive, then select S.M.A.R.T. Test.
- Choose Short Test and click Start.
On Windows (before installing in the NAS): Use a direct SATA connection where possible; SMART visibility and self-test support through a USB-to-SATA adapter depend on the adapter's bridge chipset and the diagnostic software. Open CrystalDiskInfo (free, from crystalmark.info) and check the Health Status. A yellow Caution or red Bad state indicates an immediate problem. For manufacturer-specific diagnostics, use SeaTools 5 for Seagate drives or Western Digital Kitfox for WD hard drives, and run the available short or quick diagnostic.
Both Synology and QNAP allow SMART tests on drives installed in bays that have not yet been assigned to a storage pool. Install the drive, run the test, then create the pool once all drives have passed.
Step 3: Run the Extended SMART Self-Test
The SMART extended self-test (also called a long self-test) is a comprehensive test run by the drive's firmware that reads every sector on the drive surface and tests the head, actuator, and electronics under sustained load. Extended-test duration varies by drive model, capacity, interface, system load and test implementation; use the estimate reported by the drive or diagnostic tool, and allow for more than 20 hours on high-capacity drives. This is the most important single test to run on a new drive and should be completed before the drive enters service.
On Synology DSM:
- Open Storage Manager > HDD/SSD tab.
- Click the drive, then Health Info.
- Choose Extended Test and click Run.
- DSM will notify by email (if configured) when the test completes. Results appear in the Health Info tab.
On QNAP QTS:
- Open Storage and Snapshots > Storage > Disks.
- Select the drive, then S.M.A.R.T. Test.
- Choose Extended Test and click Start.
- QTS will notify on completion via the notification system.
On Windows, use a current manufacturer diagnostic such as SeaTools 5 or Western Digital Kitfox and select the supported long diagnostic or drive self-test. CrystalDiskInfo can display SMART data but does not start a long self-test.
Interpreting results: A pass result with no SMART errors is the expected outcome for a healthy new drive. Any of the following in the post-test SMART attribute report are failure indicators for a drive sold as new:
- Reallocated Sectors Count (attribute 5) above 0: The drive has already remapped defective sectors. This is a defective product.
- Reallocated Event Count (attribute 196) above 0: Same implication as above.
- Current Pending Sectors (attribute 197) above 0: Sectors flagged for reallocation that the drive has not yet successfully rewritten.
- Uncorrectable Sector Count (attribute 198) above 0: Sectors that could not be read and could not be reallocated.
Step 4: Check the SMART Baseline Before Installing
After completing the extended self-test, read the full SMART attribute set for the drive and save the values as a baseline. This baseline is useful if the drive develops problems later and you need to determine whether a problem is new or pre-existing.
The most important SMART attributes to record:
- Attribute 5 (Reallocated Sectors Count): Should be 0 on a new drive.
- Power On Hours can help identify possible prior use, but interpret the value using documentation for the exact drive model rather than applying a universal 50-hour cutoff. Unexpectedly high Power On Hours may indicate prior use and should be queried with the seller, but the value alone does not prove that a drive was refurbished or previously returned.
- Attribute 12 (Power Cycle Count): Should be very low on a new drive. A high power cycle count combined with significant power-on hours on a drive sold as new is a clear red flag.
- Attribute 187 (Reported Uncorrectable Errors): Should be 0.
- Attribute 197 (Current Pending Sectors): Should be 0.
- Attribute 198 (Uncorrectable Sector Count): Should be 0.
Save this data as a screenshot from CrystalDiskInfo, DSM Health Info, or the manufacturer tool. If the drive develops problems later, having the baseline makes it clear what the drive's state was when new, which directly supports any warranty claim with the retailer.
Step 5: Optional Full Surface Scan
A full surface scan reads every sector of the drive at the operating system level, independent of the drive's own firmware. It is the most thorough test because it exercises the drive under real-world read conditions and can catch surface defects the drive's self-test may not expose. For most home NAS builds, the SMART extended test combined with the NAS platform's health check is sufficient. For anyone building a NAS that will hold irreplaceable data or will not have an offsite backup immediately available, the surface scan adds meaningful confidence.
On Windows: Victoria provides graphical surface scanning. HD Tune's free 2.55 build is from 2008 and officially lists support only through Windows 7; the current HD Tune Pro supports modern Windows but is a paid product after its trial. Victoria maps the full drive surface and colour-codes sectors by read speed and error status, providing a visual representation that is immediately interpretable. Download from the official developer sites.
Do not run badblocks -n against a mounted or otherwise in-use device. On Synology, prefer supported Storage Manager diagnostics; any offline surface test must target a positively identified, unmounted drive outside the storage pool, and reported errors require checking the media, connection, controller and power path.
Time considerations: A full surface scan on a 4TB drive at typical HDD read speed takes approximately 6-8 hours. On a 12TB drive, 18-24 hours. Run this test overnight or over a weekend. It does not require supervision once started.
Troubleshooting: What to Do When a Test Fails
Drive fails the quick SMART test: Do not use this drive. Power it down, repackage it, and return it to the retailer. A drive that fails its own self-test within the warranty period is a clear defective product. Under Australian Consumer Law, the retailer must provide an appropriate remedy; whether the remedy is repair, replacement or refund depends on whether the failure is major or minor. A screenshot or diagnostic log can support the claim, but the retailer may still assess the drive before providing a remedy.
Drive shows non-zero reallocated sectors on a new drive: Return it. A drive with reallocated sectors is not suitable for a NAS RAID array, regardless of whether it otherwise appears functional. On a new drive, a non-zero reallocated-sector count is a serious warning and justifies manufacturer diagnostics and contacting the seller, but it does not by itself establish a universal warranty-failure threshold.
Drive shows pending sectors but passes the extended test: This is a borderline case. An extended SMART self-test is a diagnostic scan and does not generally rewrite pending sectors. If pending sectors remain, follow the drive manufacturer's diagnostic and replacement guidance rather than assuming the test will clear them. If pending sectors remain after the extended test, return the drive.
Drive disconnects or disappears during testing: A disconnect during testing requires checking the drive, cable or adapter, power delivery, host port or NAS slot. Re-test with a known-good connection and use the manufacturer's diagnostics before concluding that the drive itself is faulty. Power cycle the drive and retry. If it disconnects again, return it. Do not attempt to add an intermittently disconnecting drive to a RAID array.
Test takes significantly longer than expected: Hard surface drive test time scales with data density, and any slow-reading sectors add time. A test taking 2-3x longer than the manufacturer's estimated test duration may indicate marginal surface areas. After the extended test completes, examine SMART attributes 187, 197, and 198 closely before deciding whether to proceed.
Related reading: our NAS buyer's guide and our NAS hard drive guide.
Free tools: Drive Failure Risk Calculator and RAID Rebuild Risk Calculator. No signup required.
See also: our complete Synology NAS Australia guide.
See also: our complete QNAP NAS Australia guide.
Do I really need to test new drives if they come with a 3-year warranty?
Yes, because the warranty covers the drive hardware, not your data. If an untested drive fails six weeks after installation during a RAID rebuild and takes an adjacent drive with it, the warranty will replace the drives. It will not recover your data, and professional RAID data recovery in Australia starts at $3,000 for physical failures. The 6-20 hours spent testing new drives before installation is a fraction of the cost of a single data recovery event. Testing is the cheap insurance that the warranty does not provide.
How long does drive testing take for a typical NAS build?
A SMART quick test takes 2-5 minutes per drive. A SMART extended self-test takes 3-20 hours per drive depending on capacity: roughly 3-6 hours for a 4TB drive, 6-12 hours for an 8-10TB drive, and 12-18 hours for a 12-16TB drive. For a 4-bay NAS with 4TB drives, testing all four drives sequentially takes 12-24 hours. If you have a PC with multiple SATA ports available, testing two drives simultaneously halves the calendar time. The testing does not require active supervision once started.
Can I run the SMART tests inside the NAS before setting up the RAID?
Yes, and this is the recommended approach for Synology and QNAP NAS. Install the drive in the NAS bay without creating a storage pool. In Synology DSM, the drive appears in Storage Manager > HDD/SSD as an unassigned drive and you can run Health tests on it directly. QNAP QTS similarly allows SMART tests on drives not yet assigned to any storage pool. Running the test in the NAS is convenient and avoids needing a separate PC or USB adapter. Do not create the storage pool until all drives have been tested and passed.
What is CrystalDiskInfo and where do I get it?
CrystalDiskInfo is a free Windows tool that reads and displays SMART data from supported connected drives; support for USB bridges, NVMe devices and RAID controllers is incomplete. It provides a Health Status rating (Good, Caution, Bad) based on SMART attribute values and displays all individual SMART attributes with current and worst-case values. It is the most widely used free drive health tool for Windows users. Download it from the developer's official site (crystalmark.info) or from reputable software repositories like Ninite. Always download from an official source rather than third-party download sites.
Should I run the extended test on SSDs as well as hard drives?
Yes, for any SSD being added to a NAS storage pool or SSD cache. SSD self-test support and duration vary by protocol, model, manufacturer and NAS platform; some SSDs do not support the same extended SMART test used for SATA hard drives. For SSDs, use the health indicators and diagnostics documented by the SSD manufacturer; HDD-style reallocated, pending and uncorrectable-sector attributes are not universal across SATA and NVMe SSDs. and catching them before the SSD is in active NAS use is always preferable to discovering the problem after data has been written to the drive.
Can I test drives I bought from a marketplace seller?
Yes, and you should, with extra attention to the Power On Hours SMART attribute. Unexpectedly high Power On Hours may indicate prior use and should be checked against documentation for the exact model and raised with the seller, but the value alone is not conclusive proof. Drives sourced from non-primary retail channels carry additional risk of being refurbished, returned, or previously used. If the SMART data shows signs of prior use, this is grounds for a return under Australian Consumer Law, which applies to any business seller operating in Australia regardless of the stock origin. Screenshot the SMART data and the original product listing before contacting the seller.
Before testing, make sure your new drives are actually NAS-suitable. The SMR vs CMR guide covers which current drive models are safe for RAID and which to avoid, including the WD Red SMR models still appearing in some AU retail channels.