Iscsi - ZyXEL Communications NAS326 User Manual

Table 36 S.M.A.R.T. Attributes (continued)
ATTRIBUTE
ID
NAME
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

5.4 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 network, data
transmission and storage management can be processed through the network. In other words, you can
access and manage the target the same way as a locally attached drive.
In the following example, a branch office has a NAS named NAS1. You want to expand your data
storage capacity by accessing an iSCSI LUN (Logical Unit Number) volume called VOL1 on NAS1 over
the Internet. Your computer is the iSCSI initiator and the NAS is the iSCSI target. When the initiator is
successfully connected to the target, your computer can use VOL1 on the NAS as its own internal
storage.
Chapter 5 Storage Manager
BETTER DESCRIPTION
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.
NAS Series User's Guide
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