Users Guide

Table Of Contents
Concatenated, see Number Of Physical Disks Per Virtual Disk. Concatenated does not provide data redundancy or
affect the read/write performance.
Select RAID 0 for striping. This selection groups n disks together as a large virtual disk with a total capacity of n disks.
Data is alternately stored in the disks so that they are evenly distributed. Data redundancy is not available in this mode.
Read/write performance is enhanced.
Select RAID 1 for mirroring disks. This selection groups two disks together as one virtual disk with a capacity of one
single disk. The data is replicated on both disks. When a disk fails, the virtual disk continues to function. This feature
provides data redundancy and good read performance, but slightly slower write performance. The system must have at
least two physical disks to use RAID 1.
Select RAID 5 for striping with distributed parity. This selection groups n disks together as one large virtual disk with a
total capacity of (n-1) disks. When a disk fails, the virtual disk continues to function. This feature provides better data
redundancy and read performance, but slower write performance. The system must have at least three physical disks to
use RAID 5.
Select RAID 6 for striping with additional distributed parity. This selection groups n disks as one large virtual disk with
a capacity of (n- 2) disks. The virtual disk remains functional with up to two disk failures. RAID 6 provides better read
performance, but slower write performance. The system must have at least four physical disks to use RAID 6.
Select RAID 10 for striping over mirror sets. This selection groups n disks together as one large virtual disk with a
total capacity of (n/2) disks. Data is striped across the replicated mirrored pair disks. When a disk fails, the virtual
disk continues to function. The data is read from the surviving mirrored pair disk. This feature provides the best failure
protection, read and write performance. The system must have at least four physical disks to use RAID 10.
Select RAID 50 to implement striping across more than one span of physical disks. RAID 50 groups n*s disks as one
large virtual disk with a capacity of s*(n-1) disks, where s is the number of spans and n is the number of disks within
each span.
Select RAID 60 to implement striping across more than one RAID 6 span. RAID 60 Groups n*s disks as one large virtual
disk with a capacity of s*(n-2) disks, where s is the number of spans and n is the number of disks within each span. RAID
60 provides increased data protection and better read performance, but slower write performance.
5. Click Continue.
Create Virtual Disk Express Wizard Step 2
The Create Virtual Disk Express Wizard - <Controller Name> page displays the summary of attributes of the selected RAID
level. The attributes include Bus Protocol, Stripe Element Size, Read Policy, and the selected physical disk. The default
values of the virtual disk attributes excluding the RAID level are recommended for the selected RAID level.
1. In the Name field, type a name for the virtual disk.
The virtual disk name can contain only alphanumeric characters, spaces, dashes, and underscores. The maximum length
depends on the controller. In most cases, the maximum length is 15 characters. The name cannot start with a space or end
with a space.
NOTE:
It is recommended that you specify a unique name for each virtual disk. If you have virtual disks with the same
name, it is hard to differentiate the generated alerts.
NOTE: If a physical disk is receiving a SMART alert, it cannot be used in a virtual disk. For more information on SMART
alerts, see Monitoring Disk Reliability On RAID Controllers.
2. In the Size field, type the size of the virtual disk.
The virtual disk size must be within the minimum and maximum values displayed near the Size field. For information on how
the maximum virtual disk size is calculated, see Calculation For Maximum Virtual Disk Size.
In some cases, the virtual disk is slightly larger than the size you specify. The Create Virtual Disk Wizard adjusts the size
of the virtual disk to avoid rendering a portion of the physical disk space unusable.
3. Click Finish to complete the virtual disk creation.
For PERC H700 and PERC H800 controllers, if any of the drives you selected is in the spun down state, the following
message is displayed:
The below listed physical drive(s) are in the Spun Down state. Executing this task on
these drive(s) takes additional time, because the drive(s) need to spun up.
Virtual Disks
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