Installation & Configuration Connecting SCSI Cables and Terminators

Connecting SCSI Cables and Terminators

CAUTION! Before connecting SCSI cabling, shut down the host, power-off the host, then power-off the storage system.

CAUTION! If your host has an HP 28696A adapter, you must have current firmware, or the differential (DF) disk modules will not be hot pluggable. Contact your HP service representative to get the current version.

NOTE!

To optimize SCSI bus performance:

∙The cable between bus A and bus B must be 0.9 meters in length minimum.

∙The cable between two A33xxAx storage systems must be 2.5 meters in length minimum.

The storage system contains two separate internal SCSI buses: bus A and bus B (see Figure 10). These buses are isolated, so two different SCSI interfaces can be supported in the same storage system. Bus A supports four devices in bay A (slots A1 through A4). Bus B supports four devices in bay B (slots B1 through B4). When a single bus is required, a 0.9-meter SCSI cable can be used to connect bus A and bus B, forming one bus that supports eight devices.

A SCSI bus consists of the following components. All of these components must be of the same type, single-ended (SE) or fast/wide differential (DF):

∙a host bus adapter (HBA) card

∙devices on the bus

∙SCSI cabling

∙a SCSI terminator (SF or DF)

Table 2 shows the SCSI bus requirements for the storage system.

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Installation