Thecus N8810U series, Руководство пользователя

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This is excellent for com plet e dat a securit y.
RAI D 5
RAI D 5 offer s dat a securit y and it is best suit ed for net w orks t hat perform m any
sm all I / O t ransact ions at t he sam e t im e, as w ell as applicat ions t hat require dat a
secu rit y such as office aut om at ion and online cu st om er service. Use it also for
applicat ions w it h high read r equest s but low w r it e request s.
RAI D 5 includes disk st r iping at t he byt e lev el and parit y inform at ion is w rit t en t o
sev eral hard disk drives. I f a hard disk fails t he syst em uses parit y st or ed on each
of t he ot h er hard disks t o r ecr eat e all m issing infor m at ion.
RAI D 6
RAI D 6 is essent ially an ext en sion of RAI D level 5 w hich allow s for addit ional fault
t olerance by using a second independent dist ribut ed parit y sch em e ( dual parit y)
Dat a is st riped on a block level acr oss a set of drives, j ust like in RAI D 5 , and a
second set of parit y is calculat ed and w rit t en acr oss all t he drives; RAI D 6 pr ovides
for an ext rem ely high dat a fault t olerance and can sust ain t w o sim ult aneous drive
failures.
This is a perfect solut ion for m ission crit ical applicat ions.
RAI D 1 0
RAI D 10 is im plem ent ed as a st riped array w hose segm ent s are RAI D 1 arrays.
RAI D 10 has t h e sam e fault t olerance as RAI D lev el 1.
RAI D 10 has t h e sam e overhead for fault - t olerance as m irr oring alone. High I / O
rat es ar e achieved by st riping RAI D 1 segm ent s.
Under cert ain circum st ances, RAI D 10 array can sust ain up t o 2 sim ult aneous drive
failures
Excellent solut ion for applicat ions t hat w ould have ot herw ise gone w it h RAI D 1 but
need an addit ional perform ance boost .
RAI D 5 0
A RAI D 50 com bines t he st raight block- level st riping of RAI D 0 w it h t he dist ribut ed
parit y of RAI D 5 . This is a RAI D 0 array st riped acr oss RAI D 5 elem ent s. I t r equires
at least 6 drives.
RAI D 6 0
A RAI D 60 com bines t he st raight block- level st riping of RAI D 0 w it h t he dist ribut ed
double parit y of RAI D 6 . That is, a RAI D 0 ar ray st riped across RAI D 6 elem ent s. I t
requires at least 8 disks.
JBOD
Alt hough a concat enat ion of disks ( also called JBOD, or " Just a Bunch of Disks" ) is
not on e of t he num ber ed RAI D lev els, it is a popular m et hod for com bining m ult iple
physical disk drives int o a single virt ual one. As t he nam e im plies, disks are m er ely
concat enat ed t oget her, end t o beginning, so t hey appear t o be a single large disk.
As t he dat a on JBOD is not prot ect ed, one drive failure could result t ot al dat a loss.
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