Dell 4100/180, 4100/200 manual Installing a Scsi Device, Prepare the drive for installation

SCSI ID Numbers

Each device attached to the Ultra/Narrow SCSI host adapter must have a unique SCSI identification (ID) number from 0 to 7.

When SCSI devices are shipped from Dell, the default SCSI ID numbers are assigned as follows:

•The computer’s built-in Ultra/Narrow SCSI host adapter is configured through the basic input/output system (BIOS) as SCSI ID 7.

•A SCSI tape drive is configured as SCSI ID 6 (the default ID number for a tape drive).

•A SCSI CD-ROM drive is usually configured as SCSI ID 5.

NOTE: There is no requirement that SCSI ID numbers be assigned sequentially or that devices be attached to the cable in order by ID number.

Device Termination

SCSI logic requires that the two devices at opposite ends of the SCSI chain be terminated and that all devices in between be unterminated.

Before installing SCSI devices in the computer, you must configure the terminators on the SCSI device(s) to con- form to the following guidelines:

•A single SCSI device (such as the standard CD-ROM drive) is terminated.

•If two or more SCSI devices are installed, connect the devices as follows:

—Attach one of the devices to the end connector on the SCSI cable, and leave the terminator enabled on that device.

—The other end of the SCSI cable connects to the com- puter’sbuilt-inUltra/NarrowSCSIhostadapteror toan optional SCSI host adapter card.

—Disable the terminators on all other devices you attach to the cable.

The standard SCSI CD-ROM drive is configured as the last device on the SCSI cable. Therefore, any additional devices attached to the cable should have their termina- tors disabled.

See the documentation provided with the SCSI device for information on disabling the device’s terminator.

SCSI Cable

CAUTION: Dell recommends that you use only SCSI cables purchased from Dell. SCSI cables purchased elsewhere are not guaranteed to work reliably with the Dell PowerEdge 4100 systems.

The 50-pin Ultra/Narrow SCSI cable has five connectors:

•The connector at the end of the cable farthest away from the other four connectors attaches to the SCSI host adapter connector labeled “SCSI CD-ROM” on the system board.

•The four connectors on the cable attach to devices in the external drive bays.

Installing a SCSI Device

To install an external SCSI device that uses the built-in Ultra/Narrow SCSI controller, follow these steps:

1.Prepare the drive for installation.

Ground yourself by touching an unpainted metal sur- face on the back of the computer, unpack the drive, and compare the jumper and switch settings with those in the drive documentation. (See “SCSI Con- figuration Information” found earlier in this chapter for information on setting the drive’s SCSI ID num- ber and enabling termination [if required].) Change any settings necessary for this system’s configu- ration.

If the drive does not already have drive rails attached, attach a drive rail to each side of the drive. Orient the drive rails as shown in Figure 9-6. Secure each drive rail to the drive with a screw in each of the lower slotted screw holes on the drive rail.

9-4 Dell PowerEdge 4100/180 and 4100/200 Systems Installation and Troubleshooting Guide