Installation

☛Note

In order to ensure an error free environment, the proper cable type designed for a certain SCSI speed must be used, please refer to Table 2-3 on page 2-15.

☛Note

To avoid problems caused by mixing drive types, please refer to “Limitations on Mixing SCSI Drives” on page 2-16.

SCSI Termination

Each end of a SCSI bus must be terminated to maintain proper voltage levels for SCSI control and data signals. The device used for this purpose is called a terminator. Termination devices can be built into a controller, a SCSI device, or attached to the end of a SCSI bus.

The AcceleRAID 170 controller is equipped with automatic SCSI bus termination circuitry. If the controller is at the end of a SCSI bus, it automatically enables on-board termination. The controller can also detect whether single-ended (SE) or low-voltage differential (LVD) termination is required, and can automatically configure the appropriate termination type.

The end of the SCSI bus farthest from the controller must be terminated if SCSI devices are connected to the SCSI channel. See Figure 2-9for an example of a SCSI device configuration connected to the internal SCSI channel.

☛Note

When connecting SCSI devices, it is better to terminate the ends of the SCSI bus itself, rather than to terminate the end devices on the bus. This allows hot swap devices to be added or removed from the SCSI bus without affecting termination.

Manual No. 775064

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