Why does my NAS show an 'Abnormal' S.M.A.R.T. status but IHM reports the drive as 'Healthy'?
Applicable Products
QTS, QuTS hero, Storage & Snapshots
Overview
QNAP NAS systems support both S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology) and IronWolf Health Management (IHM) to monitor the health of installed hard drives. Occasionally, these two systems may report different health statuses for the same drive, which can lead to confusion.
Explanation
Understanding the Differences
S.M.A.R.T. is an industry-standard technology built into most hard drives. It reports drive health based on various measurable attributes, such as reallocated sectors, read errors, and spin retries. A warning from S.M.A.R.T. typically means that the drive has already shown some degree of physical degradation, such as bad blocks or early-stage mechanical issues.
IHM is a Seagate-specific system that supplements S.M.A.R.T. data with environmental and workload analysis. It uses predictive models to identify patterns that may lead to future failure but may not flag all raw S.M.A.R.T. attribute warnings.
In some cases, S.M.A.R.T. may issue a warning due to minor errors or aging indicators, while IHM still considers the drive “healthy” because the errors have not yet reached a critical threshold in its predictive model.
Recommendation
If your S.M.A.R.T. status shows “Warning” or “Abnormal”, even when IHM says the drive is “Healthy”, we strongly recommend the following actions:
Back up your data immediately.
Monitor the S.M.A.R.T. attributes such as:
Reallocated sector count
Current pending sectors
Uncorrectable sector count
Run a Complete S.M.A.R.T. Test from Storage & Snapshots > Disks > Health Info to check for ongoing degradation.
Replace the drive if your data is important or if the S.M.A.R.T. warnings persist or increase over time.
Even minor S.M.A.R.T. warnings can be early signs of a failing drive, and it is safer to replace the drive proactively rather than risk sudden failure later.
