IBM SG24-5131-00 manual Adapter Scsi ID and Termination change

#2902

#2426

7135-110 #2902 7135-110

Controller 1 RAID Controller 1 cable

#2902

Controller 2 RAID Controller 2

#2902

#2426

#2902

#2416 (16-bit)

cable

#2902

#2416 (16-bit)

#2416 (16-bit)

#2426

#2424

#2416 (16-bit)

#2426

#2416 (16-bit)

T

T

#2416 (16-bit)

#2416 (16-bit )

T

T

Maximum total cable length: 25m

#2416 (16-bit)

Figure 11. 7135-110 RAIDiant Arrays Connected on Two Shared 16-Bit SCSI Buses

3.3.2.3 Adapter SCSI ID and Termination change

The SCSI-2 Differential Controller is used to connect to 8-bit disk devices on a shared bus. The SCSI-2 Differential Fast/Wide Adapter/A or Enhanced SCSI-2 Differential Fast/Wide Adapter/A is usually used to connect to 16-bit devices but can also be used with 8-bit devices.

In a dual head-of-chain configuration of shared disks, there should be no termination anywhere on the bus except at the extremities. Therefore, you should remove the termination resistor blocks from the SCSI-2 Differential Controller and the SCSI-2 Differential Fast/Wide Adapter/A or Enhanced SCSI-2 Differential Fast/Wide Adapter/A. The positions of these blocks (U8 and U26 on the SCSI-2 Differential Controller, and RN1, RN2 and RN3 on the

Cluster Hardware and Software Preparation 77