Maximizing Capacity; Maximizing Drive Availability; Table 7-7. Drives And Capacities For Each Raid Level; Table 7-8. Fault Tolerance Features For Raid Levels 0, 1 And - Dell PowerEdge Expandable RAID Controller 3 User Manual

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Confi gur ing PERC 3

Maximizing Capacity

RAID 0 achieves maximum drive capacity, but does not provide data
redundancy. Maximum drive capacity for each RAID level is shown below.
original equipment manufacturer (OEM) level firmware that can span up to
four logical drives is assumed. Table 7-7 displays the drives required, and
capacity for the various RAID levels.
Ta b l e 7 - 7 . D r i v e s a n d C a p a c i t i e s f o r E a c h R A I D L e v e l
RAID Description
Level
0 Striping without
parity
1 Mirroring
5 Striping with
floating parity
drive
10 RAID 1 and
striping
50 RAID 5 and
striping

Maximizing Drive Availability

You can maximize the availability of data on the physical disk drive in the
logical array by maximizing the level of fault tolerance. The levels of fault
tolerance provided by the RAID levels are shown in Table 7-8.
Ta b l e 7 - 8 . Fa u l t To l e r a n c e Fe a t u r e s f o r R A I D L e v e l s 0 , 1
a n d 5
RAID Fault Tolerance Protection
Level
0 No fault tolerance
1 Disk mirroring, which provides 100% data redundancy.
Drives Capacity
Required
1 – 32 (Number of disks) X (capacity of
smallest disk)
2 (Capacity of smallest disk) X (1)
3 – 32 (Number of disks) X (capacity of
smallest disk) - (capacity of 1
disk)
4 – 16 (Number of disks) X (capacity of
(Must be a smallest disk) / (2)
multiple of
2)
6 – 256 (Number of disks) X (capacity of
(Must be a smallest disk) – (capacity of 1
multiple of disk X number of arrays)
arrays)