HP Command View EVA Software - Manual (Page 29)

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Available, Vraid5. Shows the estimated capacity, if the entire disk group was used for Vraid5
virtual disks.
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Available, Vraid6. Shows the estimated capacity, if the entire disk group was used for Vraid6
virtual disks.
XCS 10000000 or later
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Total capacity. Shows the formatted physical disk drive capacity of the disk group.
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Allocated capacity. Shows the amount of disk group capacity that is being used for virtual
disks.
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Available capacity (estimated). Shows the capacity remaining in a disk group if all new virtual
disks were to be created as either Vraid0, Vraid1, Vraid5, or Vraid6.
◦ Physical. This value is estimated from various factors such as the number and size of
virtual disks that might typically be created. The actual available physical capacity can
be more or less than the estimate.
◦ Thin provisioning. This value is based on the maximum addressable storage space of the
storage system.
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Requested capacity. Shows the amount of space in disk group that has been requested for
virtual disks.
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Oversubscribed capacity. Shows the amount of space requested via thin provisioning that
exceeds the physical capacity that can be allocated.
Redundancy (Vraid) levels
The redundancy (Vraid) level for a virtual disk determines the virtual disk's availability (data
protection) and influences its I/O performance. If you are using XCS 09500000 or earlier, the
Vraid type cannot be changed after a virtual disk is created. For information about changing the
Vraid level on storage systems running XCS 10000000 or later, see
“Online virtual disk migration”
(page 33) .
NOTE: HP strongly recommends that you use Vraid6 if you are using disk drives with a physical
capacity of 1 TB or greater.
Vraid levels are:
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Vraid0. Is optimized for speed and disk space utilization, but provides no redundancy.
IMPORTANT: HP does not recommend using Vraid0 when high availability is required.
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Vraid1. Is optimized for speed and high redundancy, but requires twice the disk space of
other Vraid levels. Vraid1 provides sufficient data redundancy to recover from a single disk
drive failure. However, if your system uses large capacity disk drives (1TB or larger),
reconstruction time may increase the risk of a second disk drive failure occurring prior to the
completion of reconstruct.
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Vraid5. Is optimized for speed, disk space utilization, and moderate redundancy. Vraid5
provides sufficient data redundancy to recover from a single disk drive failure. However, if
Redundancy (Vraid) levels 29