Specifications

Chapter 2. Architecture and technical overview 83
2.9.2 Triple split backplane
The triple split backplane mode offers three sets of two disk drives each. This mode requires
#1815 internal SAS cable, a SAS cable #3679, and a SAS controller, such as #5901.
Figure 2-24 shows how the six disk bays are shared with the triple split backplane mode. The
PCI adapter that drives two of the six disks can be located in the same Power 770 (or
Power 780) CEC enclosure as the disk drives or adapter, even in a different system enclosure
or external I/O drawer.
Figure 2-24 Triple split backplane overview
Although SSDs are supported with a triple split backplane configuration, mixing SSDs
and HDDs in the same split domain is not supported. Also, mirroring SSDs with HDDs is
not possible.
2.9.3 Dual storage IOA configurations
The dual storage IOA configurations are available with internal or internal with external disk
drives from another I/O drawer. Solid-state drive (SSD) are not supported with this mode.
If #1819 is selected for an enclosure, selecting SAS cable #3686 or #3687 to support RAID
internal and external drives is necessary (Figure 2-25 on page 84). If #1819 is not selected
for the enclosure, the RAID supports only enclosure internal disks.
This configuration increases availability using dual storage IOA or high availability (HA) to
connect multiple adapters to a common set of internal disk drives. It also increases the
performance of RAID arrays. These rules apply to this configuration:
򐂰 This configuration uses the 175 MB Cache RAID - Dual IOA enablement card.
򐂰 Using the dual IOA enablement card, the two embedded adapters can connect to each
other and to all six disk drives, as well as the 12 disk drives in an external disk drive
enclosure if one is used.
P7IOC
Integrated
SAS Adapter
P7IOC
DVD
DASD
DASD
DASD
VSES
Redriver
Integrated
SAS Adapter
Integrated
SAS Adapter
Redriver
SAS Port Exp.
A
SAS Port Exp.
B
External Port
4-Port SAS Adapter