ZyXEL Communications NAME, Table, BETTER, BETTER, ATTRIBUTE, DESCRIPTION

Chapter 11 Packages

11.17.1 S.M.A.R.T Attributes

The following table describes some common S.M.A.R.T. attributes. If a higher or lower raw attribute value is better, it is indicated in the BETTER column. Since S.M.A.R.T. attributes and their definitions vary by manufacturer, refer to the hard drive manufacturer for details about the attributes your hard drive supports.

Table 93 S.M.A.R.T. Attributes

ID	ATTRIBUTE	BETTER	DESCRIPTION
	NAME
01	Read Error Rate	Low	Shows the rate of hardware read errors. If this is not zero, there is a
			problem with the disk surface or the read/write heads.
02	Throughput	High	This is the hard drive’s general (overall) throughput performance. A
	Performance		decreasing value indicates a problem.
03	Spin-Up Time	Low	This is the average number of milliseconds the hard drive took for spindle
			spin up (from zero RPM to fully operational).
04	Start/Stop Count		The total number of spindle start and stop cycles.
05	Reallocated	Low	Total number of reallocated sectors on the hard drive. When the hard
	Sectors Count		drive detects a read/write/verification error, it marks the sector as
			“reallocated” and transfers the data to a specially reserved (spare) area.
			The process is also known as remapping with “reallocated” sectors known
			as remaps. The more sectors the hard drive has to reallocate, the slower
			read and write speeds become.
06	Read Channel		This is the margin of a channel when it reads data.
	Margin
07	Seek Error Rate	Low	This is the rate of the magnetic heads’ seek errors. A failure in the
			mechanical positioning system, such as servo damage or a thermal
			widening of the disk, results in seek errors. An increasing number of seek
			errors indicate the condition of the disk surface and the mechanical
			subsystem are worsening.
08	Seek Time	High	This is an average performance indicator for the seek operations of the
	Performance		magnetic heads. Mechanical subsystem problems cause this value to
			decrease.
09	Power-On Hours	Low	This is how many hours the hard drive has been in a power-on state. The
	(POH)		raw value lists the total number of hours (or minutes, or seconds
			depending on the manufacturer).
10	Spin Retry Count	Low	This is the total number of spin start retry attempts. This is the number of
			attempts to spin up to fully operational speed the hard drive has made
			when the first attempt did not succeed. An increase in this value is an
			indicator of hard disk mechanical subsystem problems.
11	Recalibration	High	This is the number of times recalibration was requested when the first
	Retries		attempt did not succeed. A decrease in this value is an indicator of hard
			disk mechanical subsystem problems.
12	Device Power		This is the number of times the hard drive has gone through a full power
	Cycle Count		on and power off.
13	Soft Read Error	Low	This is the number of uncorrected read errors the hard drive has
	Rate		reported. If this is not zero, back up your data.
190	Airflow	Low	This indicates the temperature of the airflow measured by a Western
	Temperature		Digital hard drive.

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Media Server User’s Guide