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LaCie RAID Technology White Paper
OTHeR COnfIguRATIOnS
Concatenation
When disks are concatenated, their capacities are combined and data is written to the primary disk in the array
until is it full and then to successive disks. Concatenation provides no performance advantage or added mea-
sure of data safety. It is simply a method of combining two physical disks into one volume for greater overall
capacity.
Concatenation allows full use of the capacity of all disks in the array and most data can survive a disk failure.
Only data on the failed disk and data that is partially written on the failed disk and an operative disk is lost.
Concatenation
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Disk 1
Disk 2
Disk 3
Disk 4
LaCie Products with Concatenation Mode
LaCie 2big network
✦
LaCie Ethernet Disk
✦
LaCie 2big quadra
✦
LaCie 4big quadra
✦
How Concatenation Capacity Is
Calculated
Storage capacity in a concatenation configura-
tion is calculated by multiplying the number of
drives by the disk capacity, or C = n*d
where:
C = available capacity
n = number of disks
d = disk capacity
For example, in a concatenation array with four
drives each with a capacity of 1000GB, the to-
tal capacity of the array would be 4000GB:
C = (4*1000)
RAID 0
RAID 1
RAID 3
RAID 3+Spare
RAID 5
RAID 5+Spare
RAID 6
RAID 0+1
RAID 10
Concatenation
JBOD
RAID Selection
