Configuration settings for IBM DS5000, IBM DS4000, and IBM DS3000 systems

The system configuration interface provides configuration settings and options that can be used with the IBM Spectrum Virtualize™ clustered system.

These settings and options can have the following scope:

System
Logical unit (LU)
- The IBM Spectrum Virtualize system attempts to follow preferred ownership that is specified by the system. You can specify which controller (A or B) is used to perform I/O operations to a given LU. If the IBM Spectrum Virtualize system can see the ports of the preferred controller and no error conditions exist, the IBM Spectrum Virtualize system accesses that LU through one of the ports on that controller. Under error conditions, the ownership is ignored.
- You must enable the following options on any LUs that are mapped to the IBM Spectrum Virtualize system:
  - read caching
  - write caching
  - write cache mirroring
- You must not have caching without batteries that are enabled.