User's Manual
Page 64
S.M.A.R.T, or “Self-Monitoring, Analysis and Reporting
Technology”, is a hard disk technology that is incorporated into
some hard disk drives.
A S.M.A.R.T HDD can analyze the drive’s head, disc, motor,
circuit operation, history and default security values via
monitoring instructions in the HDD and the surveillance
software. An alarm will automatically be sent to the user when
a value is outside the scope of the security situation. Detection
parameters for a Seagate HDD, for example, are divided
into seven parts: ID detection code, Attribute Description,
Threshold, Attribute Value, Worst, Date, and Status.
ID Detection Code
ID detection codes are not uniform; different manufacturers
may assign varying attributes to an ID code number, or
increase or decrease the quantity according to the detected
parameter’s quantity. For example, an ID detection code for
Western Digital HDDs is “04”, and the procedure is Start/Stop
Count, but the procedure for the same code in a Fujitsu HDD is
the “number of times the spindle motor is activated”.
Attribute Description
Attribute Description: Name of detectable item. The
manufacturer can increase or decrease the rates. As an ATA
standard there are constant updates, sometimes different
models of the same brand may be quite different, but it is
a must to ensure that the major test items are specified by
S.M.A.R.T. (although different manufacturers may have differing
names, the essence of the monitoring is the same.)
1 Read Error Rate
2 Spin up Time
4 Start/Stop Count
5 Relocated Sector Count
7 Seek Error Rate
9 Power-on Hours Count
10 Spin-up Retry Count
194 Power temperatures
195 ECC on the Fly count
197 Current Pending Sector
Count
198 Disconnection beyond
repair
199 CRC cyclic redundancy
check
200 Write Error Count
Note: Different manufacturers and different models have
different attribute descriptions. The user does not need to
know the exact meanings, and attribute detection values are
good enough.
Threshold
This is specified by a manufacturer-calculated formula. If there
is an attribute value lower than the threshold, this means the
HDD has become unreliable and could easily lose data stored
on it. The composition and size of reliable attribute values are
different for different HDDs. It should be noted that the ATA
standard only provides some S.M.A.R.T. parameters; it does
not provide specific values. A “Threshold” value is determined
by the manufacturer based on the product’s features.
Thus, results produced by the manufacturer’s detection
software are very different from testing software in Windows
(such as AIDA32).
Attribute Value
Attribute value is the maximum normal value; the general
range is from 1 to 253. Typically, the maximum attribute value
is 100 (for IBM, Quantum, and Fujitsu) or 253 (for Samsung). Of
course, there are some exceptions, for example, some models
produced by Western Digital have two different attribute
values, and the property value is set to 200 during production,
but after that it is changed to 100.
Worst
The worst value is the largest non-normal value in the normal
operation of an HDD. It is a value calculated for an HDD’s
cumulative running. It is constantly refreshed according to
the drive’s running cycle, and it is very close to the threshold.
Whether or not the HDD is normal by S.M.A.R.T analysis
is based on the comparison with the threshold value. The
maximum value appears when using a new HDD, which
continues to decrease with everyday use or if an error happens.
Consequently, larger attribute values mean better quality and
higher reliability and smaller values mean a greater possibility
of failure.
Dates
Actual values of an HDD’s detection of items; many of the
values are cumulative values.
Status
The drive Status is current when all of the HDD’s attributes are
analyzed and compared by the S.M.A.R.T. system. It is also
important information to judge if the HDD is healthy or not.
There are three Status states: Normal, Alarm and Error, which
are closely related to the Pre-failure/advisory BIT.
REMOTE ACCESS
HARD DRIVE
Caution!
When working with electrostatic sensitive
devices such as hard disk or DVR
unit, make sure you use a static-free
workstation. Any electrostatic energy
coming in contact with the hard disk or DVR can damage
it permanently.
CAUTION: TO REDUCE THE RISK OF ELECTRIC SHOCK.
UNPLUG ALL POWER SOURCES, INCLUDING CAMERAS FROM
THE DVR BEFORE REMOVING COVER. FAILURE TO DO SO CAN
RESULT IN DAMAGE TO THE DVR OR ITS COMPONENTS AS
WELL AS INJURY OR DEATH.
The lightning ash with arrowhead symbol, within an equilateral
triangle, is intended to alert the user to the presence of un-insulated
“dangerous voltage” within the product’s enclosure that may be of
sufcient magnitude to constitute a risk of electric shock.
The exclamation point within an equilateral triangle, is intended to
alert the user to the presence of important operating and maintenance
(servicing) instructions in the literature accompanying the appliance.
CAUTION!
RISK OF ELECTRIC SHOCK
HDD S.M.A.R.T.