Areca ARC-1130 User Manual

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This technology provides users with advanced warning of Disk Drive 

failures, thus enabling the Operating System to warn Users of potential 

failure. S.M.A.R.T. was included in EIDE drives with the ATA-3 and later 

specification.

Since it was developed in 1988, the Simple Network Management 

Protocol has become the de facto standard for inter-network manage-

ment. Because it is a simple solution, requiring little code to imple-

ment, vendors can easily build SNMP agents into their products. SNMP 

is extensible, allowing vendors to easily add network management 

functions to their existing products. SNMP also separates the man-

agement architecture from the architecture of the hardware devices, 

which broadens the base of multi-vendor support. 

A volume set is a concatenation of storage elements that may be RAID 

arrays, JBODs, or simply areas of disks that are not part of RAID ar-

rays.

When a cache is operating in write-back mode, data written into the 

cache is not immediately written out to its destination in second-

ary storage unless the heuristics governing the flushing of dirty data 

demands otherwise. This methodology can improve the efficiency of 

write operations under favorable circumstances. However, its use can 

potentially lead to incoherences in a system that is not protected from 

power fluctuations or other failures.

When a cache is operating in write-through mode, data written into 

the cache is also written to the destination secondary storage devices. 

Essentially write completion does not occur until the data is written to 

secondary storage. Thus the contents of the cache and the secondary 

storage are always consistent. The advantage is that the possibility