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Chapter 2: Storage System Configurations
Table 2-1
CHALLENGE RAID Configurations
Configuration
Host
SCSI-2 Interface
SCSI-2
Bus
SPs
Feature
Basic
1
1
1
1
Applications can continue after failure of any disk module,
but cannot continue after failure of SCSI-2 interface or SP.
Dual-interface/
dual-processor
1
2
2
2
Provides highest availability and best storage system
performance for single-host configurations. Applications
can continue after any disk module fails.
Split-bus
2
2 (1 per server)
2
(1 per
server)
2
Resembles two basic configurations side by side. Each host
and its applications can continue after any disk module
fails. The host using a failed SCSI-2 interface or SP cannot
continue after failure, but the other host can. If one host,
SCSI-2 adapter, or SP fails, the other host can take over the
failed host’s disks with system operator intervention.
Dual-bus/
dual-initiator
2
4 (2 per server)
2
(1 per
server)
2
Provides highest availability and best storage-system
performance for dual-host configurations. With RAID of
any level other than 0, applications can continue after
failure of any disk module. If one host, SCSI-2 adapter, or SP
fails, the other host can take over the failed host’s disk units
with system operator intervention.
This configuration is required for Silicon Graphics
FailSafe™ and Oracle Parallel Server™ (OPS™).