Server Administrator Storage Management 8.3 User’s Guide

Virtual Disk Task: Reconfigure (Step 2 of 3)

1. Select the new RAID level for the virtual disk — The available RAID levels depend on the number or physical disks selected and the controller. The following describes the possible RAID levels:
   • Depending on the controller, Concatenated enables you to combine the storage capacity of several disks or to create a virtual disk using only a single physical disk. For information on whether the controller supports a single physical disk or two or more when using Concatenated, see Number Of Physical Disks Per Virtual Disk. Using Concatenated does not provide data redundancy nor does it affect the read and write performance.
   • Select RAID 0 for striping — This selection groups n disks together as one large virtual disk with a total capacity of n disks. Data is stored to the disks alternately so that they are evenly distributed. Data redundancy is not available in this mode. Read and 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 parity information — This selection groups n disks as one large virtual disk with a capacity of (n-2) disks. Two sets of parity information are alternately stored on all disks. The virtual disk remains functional with up to two disk failures.
   • 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.

     NOTE:

     • RAID 10 virtual disk reconfiguration is applicable only for PERC 9 family of hardware controllers with the latest firmware version.
     • Other RAID level virtual disks cannot be converted to RAID 10 virtual disks.
     • RAID 10 virtual disks cannot be converted to any other RAID level virtual disks.
     • RAID 10 virtual disk reconfiguration is supported only for even number of physical disks.
     • RAID 10 virtual disk reconfiguration is allowed for a maximum of 32 disks.
     • RAID 10 virtual disk reconfiguration operation is applicable only for single span with 32 disks.
     • RAID 10 virtual disk reconfiguration operation is not supported with Intelligent Mirroring.

     NOTE: For RAID 10 partial virtual disks, there are only two methods to increase the disk size or capacity:

     • Expanding the capacity by increasing the percentage value.
     • Adding disks into the original RAID 10 virtual disk.

2. In the Size field, type the size of the reconfigured virtual disk. The minimum and maximum allowable size is displayed below the Size field. These values reflect the new capacity of the virtual disk after any addition or deletion of physical disks which you may have chosen in Virtual Disk Task: Reconfigure (Step 1 of 3).

   NOTE: PERC S100 and S300 controllers do not allow you to change the RAID level.

3. Click Continue to go to the next page or Exit Wizard if you want to cancel.