3

Configuring the SCSI Bus

Some basic SCSI principles must be applied to correctly configure the SCSI bus on your system.

Termination

Most difficulties with the SCSI bus can be traced to improper termination and cabling.

The SCSI bus must be terminated at both ends, and only at the ends. Configure the termination on your IntraServer CompactPCI® adapter using the configuration information in the preceding chapter. Refer to the documentation for each device on the SCSI bus, to ensure:

1Devices at the ENDS of the bus have TERMINATION ENABLED

2Devices not at the END of the bus have TERMINATION DISABLED

3Use LVD/SE termination on the Ultra2 buses.

4Use active termination for Ultra Wide SCSI.

Automatic SCSI Termination

All IntraServer’s ITI-8000 Series adapters employ automatic termination. In normal cases, no operator action is required to correctly terminate the SCSI bus, provided the following rules are observed:

∙Each SCSI bus must be terminated ONLY at the ends. If the IntraServer ITI-8000 Series module is at the end of the SCSI bus, the termination will be set Automatically Enabled (the TERM light will light to indicate the module IS terminating the bus).

∙If the LVD/SE bus on an ITI-8000 Series module is located on a bus containing LVD devices, it will automatically set to

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