Iscsi - ZyXEL Communications NAS Series User Manual

Table 21 S.M.A.R.T. Attributes (continued)
ATTRIBUTE
ID
NAME
204 Soft ECC
Correction
205 Thermal Asperity
Rate (TAR)
206 Flying Height
207 Spin High
Current
208 Spin Buzz
209 Offline Seek
Performance
220 Disk Shift
221 G-Sense Error
Rate
222 Loaded Hours
223 Load/Unload
Retry Count
224 Load Friction
225 Load/Unload
Cycle Count
226 Load 'In'-time
227 Torque
Amplification
Count
228 Power-Off
Retract Cycle
230 GMR Head
Amplitude
231 Temperature
240 Head Flying
Hours
250 Read Error Retry
Rate

8.4 iSCSI

The NAS supports the iSCSI (Internet Small Computer System Interface) standard and can serve as
an iSCSI target. When the iSCSI initiator is successfully connected to an iSCSI target over an IP
Chapter 8 Storage Manager
BETTER DESCRIPTION
Low This is the number of errors corrected by software ECC (Error Correction
Code).
Low This is the number of thermal asperity errors. Thermal asperity is a read
signal spike caused by sensor temperature rise due to touching the disk
surface or contaminant particles.
This is the height of the hard drive's read/write heads above the disk
surface.
This is the quantity of high current used to spin up the drive.
This is the number of buzz routines to spin up the drive. When the arm
holding the read/write heads is stuck, the motor driving it tries to oscillate
the arm to free it. This causes an audible vibration.
This is the hard drive's seek performance during offline operations. Offline
operations are tests the drive does itself as opposed to those that an
external diagnostic tool has it do. Seek performance is how quickly the
drive moves from track to track.
Low This is how far the disk has moved relative to the spindle (this kind of
shift is usually due to shock).
Low This is the number of errors that have resulted from external vibration
and shock.
This is how long the hard drive has operated under data load (this
requires movement of the magnetic head armature).
This is how many time the magnetic head has changed position.
Low This is resistance caused by friction in mechanical parts during operation.
Low This is the total number of load cycles.
This is the total time that the magnetic heads actuator has had a load
(not been in the parking area).
Low This is the number of attempts to compensate for variations in platter
speed.
Low This is how many times the magnetic armature was automatically
retracted because the power was cut.
This is the amplitude of thrashing (or the distance of repetitive forward
and reverse head motion).
Low This is the hard drive's temperature.
This is the total time that the head has been positioning.
Low This is the number of errors in reading from the disk.
Cloud Storage User's Guide
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