DECnet/OSI for VMS

The DECnet/OSI for VMS Common Trace Facility (CTF) is a VMS utility designed to assist network managers in diagnosing and solving network problems by collecting and analyzing protocol data from networking software.

Key features and functionalities include:

1. Tracepoints and Trace Records: CTF utilizes "tracepoints" embedded within networking products. When activated, these tracepoints generate "trace records" containing user data, protocol data, and metadata like time, event codes, and the originating tracepoint's name.
2. Tracing Scope: It supports tracing both local (host-based VMS products like VAX P.S.I.) and remote (server-based products like DEC WANrouter 100/500) tracepoints, with certain restrictions on concurrent tracing types and systems.
3. Tracing Modes:
   • Detached Tracing: Collects data into a trace file for later analysis by a separate "trace server process," allowing the user to exit CTF. Ideal for large datasets or long-duration monitoring.
   • Live Tracing: Collects, analyzes, and displays trace records in real-time on the user's terminal. Suitable for smaller, immediate diagnostic tasks.
   • Snapshot Tracing: Buffers trace records in an internal circular buffer, capturing the most recent activity. These buffered records can then be written to a file or displayed on demand using the COLLECT command.
4. Data Analysis: Collected trace records, which are initially in binary format, are analyzed by product-specific routines to translate them into user-readable formats (ASCII, hexadecimal, octal) and display structured protocol information.
5. User Interface and Commands: Users interact with CTF through the TRACE utility, using commands such as START (to begin tracing, with qualifiers for mode, filtering, and output), STOP (to halt tracing), and ANALYZE (to format and display trace records from files or during live tracing). Commands can be bound to keypad keys for convenience.
6. Requirements and Considerations: Using CTF requires specific VMS privileges and consumes system resources, potentially impacting performance. The manual also provides guidance on troubleshooting common issues like lost trace records and failures to connect to remote servers.

CTF is supported by various Digital networking products for VMS, including DECnet/OSI for VMS, DEC WANrouter 100/500, VAX P.S.I., and VAX WAN Device Drivers.