Users Guide

Related links
Channel Redundancy
Virtual Disk Task: Recongure (Step 1 of 3)
Virtual Disk Considerations For PERC S100, S110, S130, And S300 Controllers
The following considerations apply when creating virtual disks:
• Space allocation — When you create a new virtual disk, the PERC S100, PERC S110, PERC S130, and PERC S300 controllers
allocate the largest area of free space on the physical disks to the new virtual disk.
• Rebuilding data — If a failed physical disk is used by both redundant and non-redundant virtual disks, only the redundant virtual
disks are rebuilt.
NOTE: For information on controller limitations, see Number Of Physical Disks Per Virtual Disk.
NOTE: When creating virtual disks using software RAID controllers, the information related to the physical disks linked to
the virtual disk is enumerated or displayed on Storage Management after a short delay. This delay in displaying the
information does not cause any functional limitation. If you are creating partial virtual disks, it is recommended that you
provide Storage Management adequate time between each partial virtual disk creation process.
NOTE: On software RAID S110 and S130 controllers, if a physical disk (SATA SSD or HDD) is removed from a virtual disk
and the same physical disk is reinserted (hot plug) into the virtual disk instantly, within a fraction of a second, then the
virtual disk state is displayed as
Ready and the physical disk state is displayed as Online. However, if the same physical
disk is reinserted after a short delay, then the virtual disk state is displayed as Degraded and the physical disk state is
displayed as Ready.
NOTE: On software RAID controllers, virtual disks can be created only with SATA drives.
Related links
Number Of Physical Disks Per Virtual Disk
Virtual Disk Considerations On Systems Running Linux
On some versions of the Linux operating system, the virtual disk size is limited to 1TB. Before creating a virtual disk that is larger than
1TB, you should make sure that your operating system supports this virtual disk size. The support provided by your operating system
depends on the version of the operating system and any updates or modications that you have implemented. In addition, you should
investigate the capacity of your peripheral devices to support a virtual disk that is larger than 1TB. For more information, see your
operating system and device documentation.
Number Of Physical Disks Per Virtual Disk
There are limitations on the number of physical disks that can be included in the virtual disk. These limitations depend on the
controller. When creating a virtual disk, the controllers support some stripes and spans (methods for combining the storage on
physical disks). Since, the number of total stripes and spans is limited, the number of physical disks that can be used is also limited.
The limitations on stripes and spans aect the possibilities for concatenation and RAID levels as follows:
• Maximum number of spans aects RAID 10, RAID 50, and RAID 60.
• Maximum number of stripes aects RAID 0, RAID 5, RAID 50, RAID 6, and RAID 60.
• Number of physical disks in a mirror is always 2. This property aects RAID 1 and RAID 10.
If RAID 50 and RAID 60, you can use a greater number of physical disks than is possible for other RAID levels. RAID 10 on a SAS
controller with rmware version 6.1 can use a maximum of 256 physical disks. However, the number of connectors on the controller
imposes limitations on how many physical disks can be included in a virtual disk when using RAID 10, RAID 50, or RAID 60. This is
because only a limited number of physical disks can be physically attached to the controller.
For information about the maximum number of physical disks supported by a virtual disk, see the virtual disk specications for the
controller in Supported Features.
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