Users Guide

Considerations Before Creating Virtual Disks
Dierent controllers have particular characteristics in the way they implement virtual disks. These characteristics may include use of disk
space, limitations on the number of virtual disks per controller, and so on. It can be helpful to understand these characteristics before
creating virtual disks on the controller.
The following sections describe controller information that applies to virtual disks:
• Virtual Disk Considerations for Controllers
• Problems Associated With Using The Same Physical Disks For Both Redundant And Non-Redundant Virtual Disks
• Virtual Disk Considerations On Systems Running Linux
• Number Of Physical Disks Per Virtual Disk
• Number Of Virtual Disks Per Controller
• Calculation For Maximum Virtual Disk Size
You may also want to review the following sections:
• RAID Controller Read, Write, Cache, And Disk Cache Policy
• Understanding Hot spares
• Controller - Supported Stripe Sizes
• Time Delay In Displaying Conguration Changes
NOTE
: In addition to this document, review the hardware documentation that is provided with the controllers. Reviewing the
hardware documentation along with this document may provide a better understanding of the controller limitations.
Virtual Disk Considerations For Controllers
In addition to the considerations described in this section, you should also be aware of the controller limitations described in Number of
Physical Disks per Virtual Disk for the following controllers:
• PERC H310 Adapter, PERC H310 Mini Monolithic, and PERC H310 Mini Blades
• PERC H700, PERC H710 Adapter, PERC H710 Mini Blades, PERC H710 Mini Monolithic
• PERC H800, PERC H810 Adapter
• PERC H330 Adapter, PERC H330 Mini Monolithic, PERC H330 Mini Blades, PERC H330 Embedded
• PERC H730P Adapter, PERC H730P Mini Monolithic, PERC H730P Mini Blades, PERC H730P Slim
• PERC H730 Adapter, PERC H730 Mini Monolithic, PERC H730 Mini Blades
• PERC H740P Adapter, PERC H740P Mini Monolithic
• PERC H830 Adapter
• PERC H840 Adapter
• PERC FD33xD/FD33xS
• PERC H730P MX
• PERC H745P MX
• PERC S140
NOTE
: The order of the controllers displayed on Storage Management may dier with the order of the controllers displayed in
the Human Interface (HII) and PERC Option ROM. The order of the controllers does not cause any limitation.
The following considerations apply when creating virtual disks:
• Creating virtual disks on controllers — When you create a virtual disk, you specify which physical disks are to be included in the virtual
disk. The virtual disk you create spans the specied physical disks. Depending on the size of the virtual disk, the virtual disk may not
consume all of the space on the physical disks. Any leftover space on the physical disks cannot be used for a second virtual disk unless
Virtual Disks
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