Rackable Systems OMNISTOR 4000f SERIES, User Manual

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Chapter 2 - Topologies and Operating Modes
JBOD Topology
20
JBOD Topology
Split Bus Dual-Loop Mode
The Split Bus Dual-Loop mode provides a basic single enclosure where the drive plane is split
into two independent six drive dual-loop FC-AL JBOD configurations. A jumper, (JP3),
located on the Disk I/O card will enabled the split bus mode. When the jumper is added,
the enclosure drive plane is configured as two independent busses.
Split Bus Dual-Loop Operating Mode Logical View
Depending upon how the host or hosts are connected to this configuration will determine
whether the operating mode provides a dual-loop and/or a redundant path solution to the
drives. If Port 1 and Port 2 of the HBA are connected to Loop A and Loop B respectively,
volume management software is required to manage the mirror drives that appear to the
operating system.
Drives are seen on the bus as follows:
n
D1 Upper card addresses drive slots 7-12 Loop A
n
D2 Upper card addresses drive slots 1-6 Loop A
n
D1 Lower card addresses drive slots 7-12 Loop B
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D2 Lower card addresses drive slots 1-6 Loop B
Disk I/O Card
(Upper - Loop A)
Disk I/O Card
(Lower - Loop B)
PBC
PBC
PBC
PBC
Loop A
Loop B
Loop A
Loop B
D1
D2
D1
D2
Drive Slots 1 - 6
Drive Slots 7 - 12