IBM 3531 manual Cabling the expansion unit

2.Install the expansion unit ID label.

a.Verify the setting of the expansion unit number switch (0-9).

b.Apply the expansion unit ID label that matches the setting for the unit ID switch in the blank label area directly to the left of the SCSI ID label.

3.Continue with “Cabling the expansion unit”.

Cabling the expansion unit

This section provides the SCSI and power cabling information. After you attach your SCSI and power cables, use the instructions provided in “Turning the expansion unit on and off” on page 3 for the initial startup of the expansion unit.

SCSI cabling information: The IBM Netfinity EXP300 comes with two ESM boards. There are two 68-pin SCSI Very High Density Connector Interface (VHDCI) connectors. From left to right as seen from the back, these connectors are for SCSI bus 2 and SCSI bus 1. (See “Rear controls, indicators, and connectors” on page 15 for the location of these connectors.) There are three ways to configure these buses.

Attention: A loss of data can occur if you change the position of internal switch 1 or internal switch 3 after storing data on the drives. Refer to “Conversion of EXP300 to a tower or from a tower” on page 25 if you previously stored data on the drives and you now want to change the configuration of your expansion unit from a rack to a tower orientation.

•To configure each bus independently:

1.Verify that option switch 3 (inside the switch card) is set to On. (See “Setting the interface options and ID settings” on page 10 for more information.)

2.Attach one external SCSI cable from the controller in the server to the SCSI- bus 1 connector.

3.Attach a second external SCSI cable from the controller in the server to the SCSI-bus 2 connector.

•To configure the expansion unit as a single 14-drive SCSI bus:

1.Verify that Option Switch 3 (inside the switch card) is set to Off. (See “Setting the interface options and ID settings” on page 10 for more information.)

2.Attach one external SCSI cable from the controller in the server to either SCSI-bus connector.

•To configure the expansion unit as a cluster of 13 drives on a single SCSI bus when using IBM ServeRAID controllers:

Note: When clustering with IBM ServeRAID adapters, you must configure all 13 disk drives on a single SCSI bus. The drive bay with SCSI ID=6 is automatically disabled to avoid an ID conflict with one of the ServeRAID controllers.

1.Verify that internal option switch 3 is set to Off. (See “Setting the interface options and ID settings” on page 10 for more information.)

2.Attach one external SCSI cable from the controller in server 1 to the SCSI- bus 1 connector.

3.Verify that the drive bay with SCSI ID=6 contains a filler panel.

4.Verify that one of the ServeRAID controllers is set to SCSI ID=6.

5.Attach a second external SCSI cable from the controller in server 2 to the SCSI-bus 2 connector.

36IBM Netfinity EXP300 - Type 3531 Hardware Maintenance Manual