Frequently Asked Questions
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Q: What is S.M.A.R.T. technology?

A: Self-Monitoring Analysis Reporting Technology (S.M.A.R.T.) is the industry-standard reliability prediction indicator for both IDE/ATA and SCSI hard disk drives. This specification is designed to offer early warning of some hard disk drive failures so critical data can be protected.

There are two kinds of hard disk drive failures: unpredictable and predictable. Unpredictable failures happen without warning. These can be caused by static electricity or handling damage. Predictable failures are the types of failures that S.M.A.R.T. will attempt to detect. These failures result from the gradual degradation of the drive's performance. 60% of drive failures are mechanical and that is the kind of failure S.M.A.R.T. is designed to predict.

Just as hard drive architecture varies from one manufacturer to another, so does the way S.M.A.R.T. is implemented on those drives. But the basic requirements are the same:

  • A S.M.A.R.T.-capable hard disk drive
  • An operating system that allows S.M.A.R.T. commands to pass through, such as:

    • Windows 3.1
    • Windows 95

  • An application that can display S.M.A.R.T. warning messages, such as:

    • IBM NetFinity Manager
    • Norton Smart Doctor from Symantec

S.M.A.R.T.-capable drives use a variety of techniques to monitor data availability. For example, a S.M.A.R.T. drive might monitor the fly height of the head above the magnetic media. If the head starts to fly too high or too low, there's a good chance the drive could fail. Other drives may monitor different conditions, such as ECC circuitry on the hard drive card or soft error rates.

S.M.A.R.T. offers cost-effective protection for your data. Using S.M.A.R.T.-capable drives helps reduce the risk of data loss. The advance warning helps to schedule the downtime necessary for drive replacement. However, as helpful as S.M.A.R.T. is, the best way to safeguard the data is to continue to make regular backups.

Troubleshooting a S.M.A.R.T. error:

If a problem is encountered, you can purchase software that will perform more detailed analysis of the hard drive. Older versions of GWScan may cause problems while scanning the S.M.A.R.T. in newer SATA hard drives.

If the computer's BIOS reports a S.M.A.R.T. error but GWScan does not report a S.M.A.R.T. error, make sure the latest version of GWScan is being used for testing. If serious errors are reported by GWScan and you are unsure how to proceed, contact a senior member of your team of your team supervisor. See escalation policy.

SMART Background:

SMART was originally developed and defined by the SFF committee in the mid 1990s. SMART had several evolutions that are sometimes referred to as SMART I, II and III. Over the years, the T13 committee has taken over responsibility for SMART and it is now specified in the ATA specification. The ATA specification does not define SMART I, II, III. WD would consider the following to be the definitions:

SMART I: Defined by SFF-8035i v1.0 specification (May 1995). SMART is calculated from on-line drive activity. On-line means the host system requested the drive to perform the activity (such as a read or write.)

SMART II: Defined by SFF-8035i v2.0 specification (April 1996). SMART is calculated from on-line and off-line drive activity. During idle periods, an off-line scan could be performed to scan the entire media of the hard drive. These off-line activities affect SMART.

SMART III: The latest SMART III technology not only monitors hard drive activities but adds failure prevention by attempting to detect and repair sector errors. While, earlier versions of the technology only monitored hard drive activity for data that was retrieved by the operating system, SMART III tests all data and all sectors of a drive by using "off-line data collection" to confirm the drive's health during periods of inactivity.

Information in this document was provided by the manufacturer.