DECserver 300 Problem Solving

This manual provides comprehensive troubleshooting guidance for the DECserver 300 terminal server's hardware and software, intended for server managers. It outlines a systematic approach to diagnosing and resolving problems, starting with initial checks and escalating to specific fault isolation.

Key troubleshooting tools and features covered include:

• Console Port: For displaying status messages crucial during server initialization and down-line loading.
• Self-Test Diagnostics: Performed on server initialization, indicating hardware issues via a seven-segment status display and a diagnostic dot.
• Seven-Segment Status Display: Shows diagnostic and software status codes, distinguishing between fatal (requiring repair) and non-fatal (allowing continued operation) errors.
• TEST Commands: Including TEST SERVICE, TEST PORT, and TEST LOOP for verifying communication with service nodes, testing individual ports/devices, and checking DECnet node communication.

The document details problem-solving procedures for various scenarios:

• Problems affecting all ports: Such as power issues, fatal hardware errors (indicated by the diagnostic dot), insufficient memory, lack of console messages, and down-line loading failures (indicated by status code 3 or specific error messages like 913 for fatal bugchecks).
• Problems with individual port devices: Including interactive terminals, PC file transfers, and line printers, with checks on power, cabling, speed, character size, and parity.
• Problems with service nodes: Addressing message timing, LAT protocol errors, authorized group mismatches, server capacity limits, and issues with service node software or availability.
• Problems with the Ethernet: Using SHOW SERVER COUNTERS and TEST LOOP commands to diagnose network transmission issues.

Finally, the manual provides guidelines for contacting Digital Equipment Corporation for service, detailing essential information to record (serial number, software version, error symptoms, troubleshooting steps taken) and procedures for repackaging hardware or forwarding software dump data.