Recommended Disk Array Configurations; Configuration Considerations - HP Surestore Disk Array 12h - And FC60 Service Manual

Recommended Disk Array Configurations

This section presents recommended configurations for disk arrays using one to six disk
enclosures. Configurations are provided for achieving high availability/high performance,
and maximum capacity. The configuration recommended by Hewlett-Packard is the high
availability/ high performance configuration. The configurations identify the number of
disk enclosures, cable connections, disk enclosure bus modes, RAID level, and volume
groupstructure.
Most of the configurations offer the highest level of availability, which means they are
capable of surviving the failure of a single disk (provided volume groups are created with
one disk module per disk enclosure), SCSI channel, SC10 disk enclosure, or controller
module. The only configurations that do not offer the highest level of availability are the
single disk enclosure configuration, and the two enclosure high capacity configuration.
These configurations cannot survive the failure of an entire disk enclosure, so they should
not be used in environments where high availability is critical.
The configurations list maximum disk capacity and usable disk capacity (with ten disk
modules installed). Configurations based on RAID 1 have less usable disk capacity than
RAID 5, but I/O performance is optimized when using RAID 1. Although the recommended
configurations presented here all contain ten disk modules, a disk enclosure can contain
two, four, eight, or ten disk modules.
The terms "LUN" and "volume group" are used interchangeably in the text and
Note
figures in this section.

Configuration Considerations

The following factors should be considered when using any of the recommended
configurations.
•
Multiple Hosts - A single host system is shown, but configurations can be adapted to
create multi-host, high availability systems. For more information on using multiple
hosts, see "Topologies for Windows NT and Windows 2000" on page 98.
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