mirror of
https://gitlab.archlinux.org/tpowa/archboot.git
synced 2024-09-20 03:50:37 +02:00
update md help
This commit is contained in:
parent
f40063abde
commit
3cbfe67d19
1 changed files with 25 additions and 25 deletions
|
@ -7,42 +7,42 @@ disks are not supported here. If a disk dies, the array dies with it.\n\n
|
|||
RAID-0:\n
|
||||
You have two or more devices, of approximately the same size, and you want\n
|
||||
to combine their storage capacity and also combine their performance by\n
|
||||
accessing them in parallel. Like in Linear mode, spare disks are not\n
|
||||
supported here either. RAID-0 has no redundancy, so when a disk dies, the\n
|
||||
accessing them in parallel. Like in Linear mode, spare disks are not sup-\n
|
||||
ported here either. RAID-0 has no redundancy, so when a disk dies, the\n
|
||||
array goes with it.\n\n
|
||||
RAID-1:\n
|
||||
You have two devices of approximately same size, and you want the two to\n
|
||||
be mirrors of each other. Eventually you have more devices, which you\n
|
||||
want to keep as stand-by sparedisks, that will automatically become a\n
|
||||
part of the mirror if one of the active devices break.\n\n
|
||||
be mirrors of each other. Eventually you have more devices, which you want\n
|
||||
to keep as stand-by sparedisks, that will automatically become a part of\n
|
||||
the mirror if one of the active devices break.\n\n
|
||||
RAID-4:\n
|
||||
You have three or more devices of roughly the same size and you want\n
|
||||
a way that protects data against loss of any one disk.Fault tolerance\n
|
||||
is achieved by adding an extra disk to the array, which\is dedicated \n
|
||||
to storing parity information. The overall capacity of the array is \n
|
||||
reduced by one disk.The storage efficiency is 66 percent. With six drives,\n
|
||||
the storage efficiency is 87 percent. The main disadvantage is poor per-\n
|
||||
formance for multiple, simultaneous, and independent read/write operations.\n
|
||||
Thus, if any disk fails, all data stay intact. But if two disks fail,all \
|
||||
data is lost.\n\n
|
||||
You have three or more devices of roughly the same size and you want a way\n
|
||||
that protects data against loss of any one disk.Fault tolerance is a-\n
|
||||
chieved by adding an extra disk to the array, which is dedicated to stor\n
|
||||
ing parity information. The overall capacity of the array is reduced by \n
|
||||
one disk.The storage efficiency is 66 percent. With six drives, the sto-\n
|
||||
rage efficiency is 87 percent. The main disadvantage is poor performance\n
|
||||
for multiple, simultaneous, and independent read/write operations. Thus,\n
|
||||
if any disk fails, all data stay intact. But if two disks fail,all data is\n
|
||||
lost.\n\n
|
||||
RAID-5:\n
|
||||
You have three or more devices of roughly the same size, you want to\n
|
||||
combine them into a larger device, but still to maintain a degree of\n
|
||||
redundancy fordata safety. Eventually you have a number of devices to use\n
|
||||
as spare-disks, that will not take part in the array before another device\n
|
||||
You have three or more devices of roughly the same size, you want to com-\n
|
||||
bine them into a larger device, but still to maintain a degree of redun-\n
|
||||
dancy for data safety. Eventually you have a number of devices to use as\n
|
||||
sparedisks, that will not take part in the array before another device\n
|
||||
fails. If you use N devices where the smallest has size S, the size of the\n
|
||||
entire array will be (N-1)*S. This "missing" space is used for parity\n
|
||||
(redundancy) information. Thus, if any disk fails, all data stay intact.\n
|
||||
But if two disks fail, all data is lost.\n\n
|
||||
RAID-6:\n
|
||||
You have four or more devices of roughly the same size and you want\n
|
||||
a way that protects data against loss of any two disks.Fault tolerance is\n
|
||||
achieved by adding an two extra disk to the array, which is dedicated to\n
|
||||
You have four or more devices of roughly the same size and you wanta way\n
|
||||
that protects data against loss of any two disks.Fault tolerance is a-\
|
||||
chieved by adding an two extra disk to the array, which is dedicated to\n
|
||||
storing parity information. The overall capacity of the array is reduced\n
|
||||
by 2 disks. Thus, if any two disks fail, all data stay intact. But if \n
|
||||
3 disks fail, all data is lost.\n\n
|
||||
RAID-10:\n
|
||||
Shorthand for RAID1+0, a mirrored striped array and needs a minimum of\n
|
||||
two disks. It provides superior data security and can survive multiple\n
|
||||
disk failures. The main disadvantage is cost, because 50% of your\n
|
||||
storage is duplication.
|
||||
Shorthand for RAID1+0, a mirrored striped array and needs a minimum of two\n
|
||||
disks. It provides superior data security and can survive multiple disk \n
|
||||
failures. The main disadvantage is cost, because 50% of your storage is du-\n
|
||||
plication.
|
||||
|
|
Loading…
Reference in a new issue