AlphaServer DS20 Ultra SCSI Internal StorageWorks Shelf Configuration Guide

This document serves as a configuration guide for converting a Compaq AlphaServer DS20 system from a single Ultra SCSI bus configuration to a split bus configuration. The process involves installing a second Ultra SCSI bus repeater card using the H8253-AA Ultra SCSI Bus Splitter Kit.

The guide covers:

• Kit Contents: A detailed list and diagram of the H8253-AA kit items, including the SCSI bus repeater card, various SCSI data and power cables, an active terminator, and cable ties.
• Configuration Diagrams: Visual representations of existing single-bus configurations (with one multi-channel or two single-channel controllers) and the desired split-bus configuration, highlighting the requirement for three SCSI controller channels in the latter.

• Step-by-Step Installation: Comprehensive instructions for the conversion, which include:

  • Safely shutting down the system and removing the enclosure covers.
  • Installing the SCSI bus repeater card into the StorageWorks shelf.
  • Connecting all necessary cabling, such as the Y power cable harness, short and long SCSI data cables, and the SCSI active terminator assembly, while also removing a specific jumper (W1).
  • Properly replacing the system enclosure covers.

• Verification: Instructions on how to confirm the successful installation by powering up the system to the SRM console prompt and using the show device command to check the updated SCSI configuration. It also notes that RAID devices will require configuration using a dedicated utility.