IBM RS/6000 SP Handbook page 281

The adapter utilizes the SSA Enhanced Loop (EL) architecture, which offers a
choice for SSA HA data protection, disk mirroring for the best performance, or
multi-initiator RAID for the lowest total system cost. SSA EL adapter architecture
enables RS/6000 SP PCI systems to share SSA storage in a multi-host SSA
environment (cluster/SP).
The Advanced SerialRAID Adapter with up to 160 MBps data transfer rate per
loop and optional 32 MB Fast-Write Cache increases the RS/6000 SP storage
performance in single-initiator and multi-initiator/multi-host environments. Boot
support is only via the AIX Network Install Manager (NIM). The adapter accepts a
32 MB Fast-Write Cache Option Card (F/C 6235) in either a one-initiator RAID or
one-initiator non-RAID application.
Feature characteristics
This feature has the following characteristics:
Up to 160 MBps data transfer rates per loop
Support for the following options:
– 8-way JBOD
– 2-way RAID 5
– 2-way RAID 10
– 1-way RAID 0
– 2-initiator Fast Write Cache with fail over (F/C 6235)
– 128 MB DIMM (F/C 6231) available for full capacity FWC with two
initiatiors
– TMSSA and fencing (used primarily by HACMP)
– Two adapters in same host on same loop - automatic adapter takeover on
– failure
– Hot spares on same loop - automatic rebuild on disk failure (RAID 5 and
RAID 10 configurations)
Interoperates with PCI SSA Multi-Initiator/RAID EL Adapter (F/C 6215), MCA
SSA
Multi-Initiator/RAID EL Adapter (F/C 6219), and Advanced SerialRAID
Adapter (F/C 6225) in JBOD and RAID 5
PCI 2.1 compatible, universal 3.3/5 volt adapter
Native and NIM boot/install from JBOD disks:
– Boot after NIM AIX install on AIX 4.2.1 and 4.3.2/n
– Boot after Native AIX install on AIX 4.3.n
Supports 48 drives per loop, 96 drives per adapter
Operates at 40 MBps on SSA link when attached to another 40 MBps capable
port
Chapter 8. PCI communication adapters
257