Infortrend RAID Controller Manual

12-2
� Fibre Interface
The controller communication is more flexible with the Fibre
controllers. Integrators may choose SCSI channels 6 and 7 or Fibre
channel(s) as illustrated below for inter-communications. Cache
synchronization over two SCSI channels - channel 6 and 7 - is
supported by firmware release 3.12 and above.
Figure 12 - 2 Redundant Configuration Using Fibre
Controllers
With Fibre-to-Fibre controllers, there are basically three choices
with inter-communications:
1. SCSI Path - The first is using SCSI channels (implemented as
channels 6 and 7) as the communications paths. The only
exception is that the 6-channel EonRAID does not support
SCSI interface on its back panel.
2. Dedicated Fibre Loops - The second is choosing one or
two Fibre channels as the dedicated communications paths.
Two for communications is recommended for the redundancy
it provides. It allows one path to fail without affecting system
operation. The controllers will shift communications to the
existing path. Dual-channel configuration offers a greater
throughput as well as enhanced performance.
3. Communications over Drive Loops - The third is
choosing all drive loops together. The controllers will
distribute the communications traffic to all drive loops.
Workflow will be balanced among loops saving channels for
drive connection. With the EonRAID 2000-6, for instance,
there can be as many as two host and four drive channels
forming the drive connectivity in two dual-loop configurations
while still benefited from controller communications.
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