The Drive Way - Setting SCSI Jumpers
(Page 3 of 10 )
To set the jumpers for a SCSI drive:
- Find the jumper block for setting the SCSI drive’s termination and ID by looking at the jumper label, which is either a sticker on the drive or etched directly on the drive. If you’re not sure about the proper configuration settings, or the device itself has no labels, check the device documentation.
- Check the SCSI ID numbers used by the other SCSI devices on the SCSI chain by identifying them onscreen during system boot or through the device documentation, and then set the drive’s SCSI ID to a free number. See Table 6-2 for more.

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| SCSI Drives Up to 15,000 RPM | Transfer Speed | Number of Devices / Cable |
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| SCSI (SCSI-1) | 5 Mbps | 8 | 50-pin |
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| | |
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| Fast SCSI (SCSI-2) | 10 Mbps | 8 | 50-pin |
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Fast Wide SCSI (SCSI-2) | 20 Mbps | 16 | 50-pin |
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Ultra SCSI (SCSI-3) | 20 Mbps | 8 | 68-pin |
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| | |
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|
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| | | |
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Ultra Wide SCSI (SCSI-3) | 40 Mbps | 16 | 68-pin |
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| | |
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Ultra-2 SCSI (SCSI-3) | 40 Mbps | 8 | 68-pin |
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| | |
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| Ultra-2 Wide SCSI (SCSI-3) | 80 Mbps | 16 | 68-pin |
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Ultra-3 SCSI (SCSI-3) | 80 Mbps | 8 | 80-pin |
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| Ultra-3 Wide SCSI or Ultra160(SCSI-3) | 160 Mbps | 16 | 80-pin |
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| Ultra320 (SCSI-SPI-4) | 320 Mbps | 16 | 80-pin |
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| Ultra640 (SCSI-SPI-5) | 640 Mbps | 16 | 80-pin |
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Table 6-2 Hard Drive Transfer Rate, Device Capacity, and Cables
Compatibility It pays to check out Microsoft’s Hardware Compatibility List (HCL) before you pick up a used hard drive. The HCL is included on the Windows 2000 or Server 2003 CD-ROM, and the most up-to-date version is located at www .microsoft.com/hwdq/hcl/. An incompatible hard drive will cause an installation failure, so it’s better to check the HCL before you start instead of after the third failed installation attempt (more on this in Chapter 9).
A recent compatibility problem that I encountered existed because Windows 2000 and Server 2003 are now true Plug-and-Play operating systems, whereas Windows NT Server, the predecessor to Windows 2000 and Server 2003, is not. If you are installing this Plug-and-Play NOS on a machine with non-Plug-and-Play devices, as is true with many systems designed for NT, the installation will fail. Non-Plug-and-Play devices include drivers that “hard-code” specific system resources, such as IRQs, to those devices. When installing a Plug-and-Play NOS, it will automatically recognize and assign resources through virtual drivers to those devices throughout the installation process. The legacy ISA device or older SCSI drive may be fine during the first part of the installation process, but at the tail end, when trying to reshuffle resources, the resulting conflict causes an installation failure. I learned to check the HCL when I attempted to install Windows 2000 on a seemingly adaptable 9GB SCSI hard drive inside an IBM Netfinity 3000 Server running Windows NT.
Other factors when using SCSI devices include jumper configurations and limited system BIOS support. There are many standards, variations of speeds and connectors (50-, 68-, and 80-pin), and no common software interface.
Any ATA device (hard drive, CD-ROM, or tape drive) has a 40-pin connector. There may be a single pin missing on the newer ATA66, ATA100, and ATA133 80-wire, 40-pin cables, but the classic ATA33 IDE cables have only 40 wires and 40 pins (see Table 6-3). Many of the faster 80-wire, 40-pin high-speed ATA cables have a single pin missing, with the coordinating hole plugged on the connector, as shown at the bottom of Figure 6-2. Be careful not to force one of these 80-wire, 40-pin cables into a “classic” 40-wire, 40-pin connector socket—effectively trying to punch the extra pin through the plug.


Figure 6-2: Each drive requires a special cable.
EIDE Drives (ATA) up to 7200 RPM | Transfer Speed | Number of Devices | Cable |
| ATA33 | 33 Mbps | 2 | 40-pin (40-wire) |
| ATA66 | 66 Mbps | 2 | 40-pin (80-wire) |
| ATA100 | 100 Mbps | 2 | 40-pin (80-wire) |
| ATA133 | 133 Mbps | 2 | 40-pin (80-wire) |
This chapter is from Build Your Own Server, by Tony Caputo (McGraw-Hill/Osborne, 2004, ISBN: 0072227281). Check it out at your favorite bookstore today. Buy this book now. |
Next: Partitions and Volumes, HBAs and RAID >>
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