ZyXEL Communications NSA221 User Manual page 270

Chapter 10 Package Management
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 81 S.M.A.R.T. Attributes
ATTRIBUTE
ID
NAME
01 Read Error
Rate
02 Throughput
Performance
03 Spin-Up Time
04 Start/Stop
Count
05 Reallocated
Sectors Count
06 Read Channel
Margin
07 Seek Error
Rate
08 Seek Time
Performance
09 Power-On
Hours (POH)
10 Spin Retry
Count
11 Recalibration
Retries
12 Device Power
Cycle Count
13 Soft Read Error
Rate
270
BETTE
DESCRIPTION
R
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.
High This is the hard drive's general (overall) throughput
performance. A decreasing value indicates a problem.
Low This is the average number of milliseconds the hard drive
took for spindle spin up (from zero RPM to fully
operational).
The total number of spindle start and stop cycles.
Low Total number of reallocated sectors on the hard drive.
When the hard 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.
This is the margin of a channel when it reads data.
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.
High This is an average performance indicator for the seek
operations of the magnetic heads. Mechanical subsystem
problems cause this value to decrease.
Low This is how many hours the hard drive has been in a
power-on state. The raw value lists the total number of
hours (or minutes, or seconds depending on the
manufacturer).
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.
High This is the number of times recalibration was requested
when the first attempt did not succeed. A decrease in this
value is an indicator of hard disk mechanical subsystem
problems.
This is the number of times the hard drive has gone
through a full power on and power off.
Low This is the number of uncorrected read errors the hard
drive has reported. If this is not zero, back up your data.
NSA221 User's Guide