Dell PowerVault MD3200 Owner's Manual page 118

attempts to choose physical disks that provide enclosure loss protection. If
you choose to create a disk group by using the Manual method, you must use
the criteria specified in Table 9-2.
Table 9-2. Criteria for Enclosure Loss Protection
RAID Level
RAID level 5
or RAID level
6
RAID level 1 Ensure that each physical disk in a mirrored pair is located in a
RAID level 0 Because RAID level 0 does not have consistency, you cannot achieve
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Configuration: Disk Groups and Virtual Disks
Criteria for Enclosure Loss Protection
Ensure that all the physical disks in the disk group are located in
different expansion enclosures.
Because a RAID level 5 requires a minimum of 3 physical disks,
enclosure loss protection cannot be achieved if your storage array has
less than 3 expansion enclosures.
Because a RAID level 6 requires a minimum of 5 physical disks,
enclosure loss protections cannot be achieved if your storage array has
less than 5 expansion enclosures.
different expansion enclosure. This enables you to have more than
two physical disks in the disk group within the same expansion
enclosure.
For example, if you are creating a six physical disk, disk group (3-
mirrored pairs), you can achieve enclosure loss protection with only
two expansion enclosures by specifying that the physical disk in each
mirrored pair are located in separate expansion enclosures. For
example:
• Mirror pair 1—Physical disk in enclosure 1, slot 1 and physical disk in
enclosure 2, slot 1.
• Mirror pair 2—Physical disk in enclosure 1, slot 2 and physical disk in
enclosure 2, slot 2.
• Mirror pair 3—Physical disk in enclosure 1, slot 3 and physical disk in
enclosure 2,slot 3.
Because a RAID level 1 disk group requires a minimum of two physical
disks, enclosure loss protections cannot be achieved if your storage
array has less than two expansion enclosures.
enclosure loss protection.