Ssa Adapters - IBM AIX HACMP SG24-5131-00 Hardware User Manual

• A maximum of 48 devices can be connected in a particular SSA loop.
• Only one pair of adapter connectors can be connected in a particular SSA
loop.
• Member disk drives of an array can be on either SSA loop.
For SSA loops that include a Micro Channel Enhanced SSA
Multi-initiator/RAID EL adapter, Feature 6215 or a PCI SSA
Multi-initiator/RAID EL adapter, Feature 6219, the following rules apply:
• Each SSA loop must be connected to a valid pair of connectors on the
SSA adapter (that is, either Connectors A1 and A2, or Connectors B1 and
B2).
• A maximum of eight adapters can be connected in a particular loop if none
of the disk drives in the loops are array disk drives and none of them is
configured for fast-write operations. The adapters can be up to eight
Micro Channel Enhanced SSA Multi-initiator/RAID EL Adapters, up to
eight PCI Multi-initiator/RAID EL Adapters, or a mixture of the two types.
• A maximum of two adapters can be connected in a particular loop if one or
more of the disk drives in the loop are array disk drives that are not
configured for fast-write operations. The adapters can be two Micro
Channel Enhanced SSA Multi-initiator/RAID EL Adapters, two PCI
Multi-initiator/RAID EL Adapters, or one adapter of each type.
• Only one Micro Channel Enhanced SSA Multi-initiator/RAID EL Adapter or
PCI SSA Multi-initiator/RAID EL Adapter can be connected in a particular
loop if any disk drives in the loops are members of a RAID-5 array, and are
configured for fast-write operations.
• All member disk drives of an array must be on the same SSA loop.
• A maximum of 48 devices can be connected in a particular SSA loop.
• Only one pair of adapter connectors can be connected in a particular loop.
• When an SSA adapter is connected to two SSA loops, and each loop is
connected to a second adapter, both adapters must be connected to both
loops.
For the IBM 7190-100 SCSI to SSA converter, the following rules apply:
• There can be up to 48 disk drives per loop.
• There can be up to four IBM 7190-100 attached to any one SSA loop.
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