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Planning for SAS RAID controller module

The SAS RAID controller module is a SAS switch and a RAID controller packaged into a single module. It is designed to enable you to share the integrated storage among all blade servers in the BladeCenter S chassis and implement a RAID solution for that storage.

Each SAS RAID controller module provides internal ports to communicate with the hard disk drives in each of the disk storage modules. In addition, the SAS RAID controller module communicates with each of the ports on the SAS expansion card option that is installed in a blade server (the SAS expansion card option provides two ports). This provides a redundant path to the SAS RAID controller modules.
Note
External ports on the SAS RAID controller module are not currently supported.
You must install two SAS RAID controller modules, one in I/O module bay 3 and the other in I/O module bay 4. In addition, you must install a SAS expansion card option in each of the blade servers that will have access to the integrated shared storage.
Note
  • Only SAS hard disk drives are supported by the SAS RAID controller module.
  • If you are installing both disk storage modules, hard disk drives should be installed evenly across the disk storage modules. Depending on your storage pool configuration, this enables you to split primary and secondary volumes so that the storage pool will remain viable if one of the storage modules goes offline.
Battery backup units provide backup of the SAS RAID controller module cache so that data is not lost in the event of a power failure. Battery backup units are required. Each battery backup unit provides backup support for one of the SAS RAID controller modules.
  • Battery backup unit 1 provides backup support for the SAS RAID controller module installed in I/O module bay 3.
  • Battery backup unit 2 provides backup support for the SAS RAID controller module installed in I/O module bay 4.
  • Defining storage pools
    The SAS RAID controller modules support the implementation of RAID 0, RAID 1, RAID 5, and RAID 0+1. Typically, you will define two storage pools.
  • Defining volumes
    After you define storage pools, you need to break the storage pools into discrete areas of storage, which are called volumes. Each blade server can access one or more of these volumes.
  • Zone for SAS RAID controller modules
    A single predefined zone configuration is available for the SAS RAID controller module. All blade servers can access both SAS RAID controller modules, and the SAS RAID controller modules have access to the hard disk drives in both disk storage modules.