Machine Log Replay guide for reproducing recorded machine events. This page positions replay as reference mode, not the main realism path.
Machine Log Replay

Replay one recorded event exactly when exact comparison matters.

Machine Log Replay feeds one recorded machine log back through the simulator so a controller or engineer can see the same recorded sequence again. It is useful, but it serves a different purpose than the main behavior model.

ModbusSim Machine Log Replay screen with a replay file loaded and active mode visible.
Machine Log Replay is for exact playback of a known captured event.

Best use cases

  • Exact replay of a known recorded event
  • A reference run for comparison
  • Regression checking against a known log
  • Proof that a specific field capture can be reproduced

Limitations

  • It does not automatically give you full-capacity coverage.
  • It does not add editable missing states.
  • It does not create generalized behavior outside the captured run.
  • It is not a reusable engineering model for new scenarios by itself.

Machine Log Replay is a replay tool, not the primary modeling tool.

Recommended workflow

  1. Load the target machine log.
  2. Confirm the log contains the scenario you want.
  3. Run the controller or monitor against the replay.
  4. Compare the replayed behavior against the active behavior model when needed.
  5. Use findings to improve the behavior model, not to replace it.

Relationship to the main behavior model

Treat replay as an evidence source, baseline source, and comparison source.

The Compressor Behavior Model remains the main mode for external-control testing because it lets the engineer combine real logs with engineer-estimated coverage and tune the full testing range.