Scsi cabling requirements, Setting scsi ids, Scsi cabling requirements setting scsi ids – IBM x Series 200 User Manual

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Installing options

•

Domain name validation to negotiate compatible data transfer speeds with each
device

•

Cyclic-redundancy checking, instead of the usual parity checking, to significantly
improve data reliability

Note:

If you install a RAID adapter, you can move the SCSI signal cable from the
SCSI connector on the SCSI adapter to an internal channel connector on the
RAID adapter to control the internal drives from the RAID adapter.

SCSI cabling requirements:

You can install five internal SCSI devices using the SCSI

signal cable that comes with your server. If you plan to attach external SCSI devices,
you must order additional SCSI cables. To select and order the correct cables for use
with external devices, contact your IBM reseller or IBM marketing representative. To
receive an indication of SCSI hard disk drive activity, you must also connect the SCSI
adapter to the SCSI LED (J3) connector on the system board. See “System and PCI
extender board options connectors” on page 35 for the location of the SCSI connector.

For information about the maximum length of a SCSI cable between the terminated
ends of the cable, refer to the American National Standards Institute (ANSI) SCSI
standards. Adhering to these standards will help ensure that your server operates
correctly.

Setting SCSI IDs:

Each SCSI device connected to a SCSI controller must have a

unique SCSI ID. This ID enables the SCSI controller to identify the device and ensure
that different devices on the same SCSI channel do not attempt to transfer data
simultaneously. SCSI devices that are connected to different SCSI channels can have
duplicate SCSI IDs.

To install external SCSI devices, you must first install an optional SCSI PCI adapter.
Refer to the information that is provided with the device for instructions to set its SCSI
ID.

With a SCSI adapter installed in your server, you can use its 68-pin SCSI connector to
connect different types of SCSI devices. The following table shows the pin-number
assignments for the SCSI connector.