Parallel Disk Array

This document describes the DECmpp 12000/Sx Parallel Disk Array (PDA), a random access, hard disk storage system designed to complement DECmpp Massively Parallel Processing systems. It covers the following key areas:

• Overview: Details PDA architecture, components, configurations, and the power/fan tray system.
• Installation: Provides site preparation specifications, hardware installation steps, and connection to the Data Parallel Unit (DPU).
• System Administration: Outlines procedures for establishing communication, configuring controllers, setting up file systems, and performing system upgrades.
• Disk Formatting: Explains the disk formatting process, the use of various FORMAT and utility commands, and reconstructing drives after failure.
• Removal and Replacement: Detailed service procedures for replacing field-replaceable units such as PCBs, disk canisters, and cables.
• Diagnostics: Covers diagnostic environments, lightpipe indicator status, and error code descriptions.
• Configuration Data: Provides reference data for controller and disk configurations.

The manual is intended for Digital Services personnel and self-maintenance customers, and includes extensive appendices with configuration data and reference pages.