IBM 86655RY - Netfinity 7600 - 8665, Hardware Maintenance Manual

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Hardware Maintenance Manual: Netfinity 7600 – Type 8665 Models 1RY, 2RY
SCSI channel connectors
The ServeRAID-4H controller has four independent SCSI channel connectors:
Channel 1, Channel 2, Channel 3, and Channel 4. Each of these SCSI channels
supports up to 15 physical devices.
Note: The battery-backup cache protects the data being stored in the ServeRAID
cache memory during a power outage or failure when using the write-back
mode.
You can attach internal SCSI devices to the Channel 1 and Channel 2 connectors. You
can attach external SCSI devices to the Channel 1, Channel 2, Channel 3, and Channel
4 connectors.
Note: The ServeRAID-4H controller does not support configurations that use both
the internal and external connectors on the same channel concurrently. For
example, you cannot use both external Channel 1 and internal Channel 1.
CAUTION:
The ServeRAID-4H controller uses a lithium battery.
CAUTION:
When replacing the lithium battery, use only IBM Part Number 38L3386 or an
equivalent type battery recommended by the manufacturer. If your system has a
module containing a lithium battery, replace it only with the same module type
Figure 1. ServeRAID-4H controller
Internal Channel 2
Internal Channel 1
External Channel 1
External Channel 2
External Channel 3
External Channel 4
Cache battery